Convert tests to karma

This change was done with Find-Replace. Additional manual
fixes exist in some tests (adding cleanups, replace some helper methods,
etc...).

This change contains only _test.js files and doesn't change any
production file.

Change-Id: I77973f7accbbd2b639beef71bcebf93e255cf8a1
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-context_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-context_test.js
index a14612b..4f931f9 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-context_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-context_test.js
@@ -1,42 +1,26 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2017 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-annotation-actions-context</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-
-<test-fixture id="basic">
-  <template>
-    <div></div>
-  </template>
-</test-fixture>
-
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import './gr-js-api-interface.js';
 import {GrAnnotation} from '../../diff/gr-diff-highlight/gr-annotation.js';
 import {GrAnnotationActionsContext} from './gr-annotation-actions-context.js';
 import {_testOnly_initGerritPluginApi} from './gr-gerrit.js';
+
 const pluginApi = _testOnly_initGerritPluginApi();
 
 suite('gr-annotation-actions-context tests', () => {
@@ -65,6 +49,7 @@
 
   teardown(() => {
     sandbox.restore();
+    el.remove();
   });
 
   test('test annotateRange', () => {
@@ -101,4 +86,4 @@
     assert.isTrue(lineNumberEl.classList.contains(className));
   });
 });
-</script>
+
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api_test.js
index e72fc63..4bbe7e5 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api_test.js
@@ -1,44 +1,33 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2016 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-annotation-actions-js-api-js-api</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-<test-fixture id="basic">
-  <template>
-    <span hidden id="annotation-span">
-      <label for="annotation-checkbox" id="annotation-label"></label>
-      <iron-input type="checkbox" disabled>
-        <input is="iron-input" type="checkbox" id="annotation-checkbox" disabled>
-      </iron-input>
-    </span>
-  </template>
-</test-fixture>
-
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import '../../change/gr-change-actions/gr-change-actions.js';
 import {_testOnly_initGerritPluginApi} from './gr-gerrit.js';
+import {html} from '@polymer/polymer/lib/utils/html-tag.js';
+
+const basicFixture = fixtureFromTemplate(html`
+  <span hidden id="annotation-span">
+    <label for="annotation-checkbox" id="annotation-label"></label>
+    <iron-input type="checkbox" disabled>
+      <input is="iron-input" type="checkbox" id="annotation-checkbox" disabled>
+    </iron-input>
+  </span>
+`);
 
 const pluginApi = _testOnly_initGerritPluginApi();
 
@@ -122,7 +111,7 @@
   });
 
   test('toggle checkbox', () => {
-    const fakeEl = {content: fixture('basic')};
+    const fakeEl = {content: basicFixture.instantiate()};
     const hookStub = {onAttached: sandbox.stub()};
     sandbox.stub(plugin, 'hook').returns(hookStub);
 
@@ -189,4 +178,4 @@
     assert.equal(listenerCalledTimes, 3);
   });
 });
-</script>
+
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils_test.js
index d01566a..85c62cb 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils_test.js
@@ -1,32 +1,21 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2019 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-api-interface</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import './gr-js-api-interface.js';
 import {getPluginNameFromUrl} from './gr-api-utils.js';
 
@@ -82,4 +71,4 @@
     });
   });
 });
-</script>
+
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-actions-js-api_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-actions-js-api_test.js
index 1d5e423..231830bd 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-actions-js-api_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-actions-js-api_test.js
@@ -1,50 +1,32 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2016 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-change-actions-js-api</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-<!--
-This must refer to the element this interface is wrapping around. Otherwise
-breaking changes to gr-change-actions won’t be noticed.
--->
-
-<test-fixture id="basic">
-  <template>
-    <gr-change-actions></gr-change-actions>
-  </template>
-</test-fixture>
-
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import '../../change/gr-change-actions/gr-change-actions.js';
 import {dom} from '@polymer/polymer/lib/legacy/polymer.dom.js';
 import {resetPlugins} from '../../../test/test-utils.js';
 import {pluginLoader} from './gr-plugin-loader.js';
 import {_testOnly_initGerritPluginApi} from './gr-gerrit.js';
+
+const basicFixture = fixtureFromElement('gr-change-actions');
+
 const pluginApi = _testOnly_initGerritPluginApi();
 
-suite('gr-js-api-interface tests', () => {
+suite('gr-change-actions-js-api-interface tests', () => {
   let element;
   let changeActions;
   let plugin;
@@ -65,7 +47,7 @@
       // Mimic all plugins loaded.
       pluginLoader.loadPlugins([]);
       changeActions = plugin.changeActions();
-      element = fixture('basic');
+      element = basicFixture.instantiate();
     });
 
     teardown(() => {
@@ -83,7 +65,7 @@
   suite('normal init', () => {
     setup(() => {
       resetPlugins();
-      element = fixture('basic');
+      element = basicFixture.instantiate();
       sinon.stub(element, '_editStatusChanged');
       element.change = {};
       element._hasKnownChainState = false;
@@ -229,4 +211,4 @@
     });
   });
 });
-</script>
+
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-reply-js-api_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-reply-js-api_test.js
index 0360f85..f545a38 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-reply-js-api_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-reply-js-api_test.js
@@ -1,45 +1,26 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2016 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-change-reply-js-api</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-<!--
-This must refer to the element this interface is wrapping around. Otherwise
-breaking changes to gr-reply-dialog won’t be noticed.
--->
-
-<test-fixture id="basic">
-  <template>
-    <gr-reply-dialog></gr-reply-dialog>
-  </template>
-</test-fixture>
-
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import '../../change/gr-reply-dialog/gr-reply-dialog.js';
 import {_testOnly_initGerritPluginApi} from './gr-gerrit.js';
 
+const basicFixture = fixtureFromElement('gr-reply-dialog');
+
 const pluginApi = _testOnly_initGerritPluginApi();
 
 suite('gr-change-reply-js-api tests', () => {
@@ -65,7 +46,7 @@
       pluginApi.install(p => { plugin = p; }, '0.1',
           'http://test.com/plugins/testplugin/static/test.js');
       changeReply = plugin.changeReply();
-      element = fixture('basic');
+      element = basicFixture.instantiate();
     });
 
     teardown(() => {
@@ -93,7 +74,7 @@
 
   suite('normal init', () => {
     setup(() => {
-      element = fixture('basic');
+      element = basicFixture.instantiate();
       pluginApi.install(p => { plugin = p; }, '0.1',
           'http://test.com/plugins/testplugin/static/test.js');
       changeReply = plugin.changeReply();
@@ -122,4 +103,4 @@
     });
   });
 });
-</script>
+
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit_test.js
index 2d87497..d8f240c 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit_test.js
@@ -1,43 +1,28 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2019 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-api-interface</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-
-<test-fixture id="basic">
-  <template>
-    <gr-js-api-interface></gr-js-api-interface>
-  </template>
-</test-fixture>
-
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import './gr-js-api-interface.js';
 import {pluginLoader} from './gr-plugin-loader.js';
 import {resetPlugins} from '../../../test/test-utils.js';
 import {_testOnly_initGerritPluginApi} from './gr-gerrit.js';
 
+const basicFixture = fixtureFromElement('gr-js-api-interface');
+
 const pluginApi = _testOnly_initGerritPluginApi();
 
 suite('gr-gerrit tests', () => {
@@ -57,7 +42,7 @@
         return sendStub(...args);
       },
     });
-    element = fixture('basic');
+    element = basicFixture.instantiate();
   });
 
   teardown(() => {
@@ -102,4 +87,4 @@
     });
   });
 });
-</script>
+
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface_test.js
index ea1ac91..0c41180 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface_test.js
@@ -1,38 +1,21 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2016 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-api-interface</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-
-<test-fixture id="basic">
-  <template>
-    <gr-js-api-interface></gr-js-api-interface>
-  </template>
-</test-fixture>
-
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import './gr-js-api-interface.js';
 import {BaseUrlBehavior} from '../../../behaviors/base-url-behavior/base-url-behavior.js';
 import {GrPopupInterface} from '../../plugins/gr-popup-interface/gr-popup-interface.js';
@@ -42,6 +25,8 @@
 import {pluginLoader} from './gr-plugin-loader.js';
 import {_testOnly_initGerritPluginApi} from './gr-gerrit.js';
 
+const basicFixture = fixtureFromElement('gr-js-api-interface');
+
 const pluginApi = _testOnly_initGerritPluginApi();
 
 suite('gr-js-api-interface tests', () => {
@@ -70,7 +55,7 @@
         return sendStub(...args);
       },
     });
-    element = fixture('basic');
+    element = basicFixture.instantiate();
     errorStub = sandbox.stub(console, 'error');
     pluginApi.install(p => { plugin = p; }, '0.1',
         'http://test.com/plugins/testplugin/static/test.js');
@@ -585,4 +570,4 @@
     });
   });
 });
-</script>
+
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-action-context_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-action-context_test.js
index 08c784ab..dda560f 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-action-context_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-action-context_test.js
@@ -1,38 +1,21 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2017 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-plugin-action-context</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-
-<test-fixture id="basic">
-  <template>
-    <div></div>
-  </template>
-</test-fixture>
-
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import './gr-js-api-interface.js';
 import {dom} from '@polymer/polymer/lib/legacy/polymer.dom.js';
 import {GrPluginActionContext} from './gr-plugin-action-context.js';
@@ -93,17 +76,28 @@
     assert.equal(div.textContent, 'foobar');
   });
 
-  test('button', done => {
-    const clickStub = sandbox.stub();
-    const button = instance.button('foo', {onclick: clickStub});
-    // If you don't attach a Polymer element to the DOM, then the ready()
-    // callback will not be called and then e.g. this.$ is undefined.
-    dom(document.body).appendChild(button);
-    MockInteractions.tap(button);
-    flush(() => {
-      assert.isTrue(clickStub.called);
-      assert.equal(button.textContent, 'foo');
-      done();
+  suite('button', () => {
+    let clickStub;
+    let button;
+    setup(() => {
+      clickStub = sandbox.stub();
+      button = instance.button('foo', {onclick: clickStub});
+      // If you don't attach a Polymer element to the DOM, then the ready()
+      // callback will not be called and then e.g. this.$ is undefined.
+      dom(document.body).appendChild(button);
+    });
+
+    test('click', done => {
+      MockInteractions.tap(button);
+      flush(() => {
+        assert.isTrue(clickStub.called);
+        assert.equal(button.textContent, 'foo');
+        done();
+      });
+    });
+
+    teardown(() => {
+      button.remove();
     });
   });
 
@@ -160,4 +154,4 @@
     });
   });
 });
-</script>
+
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader_test.js
index f10916d..5f0ee0f 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader_test.js
@@ -1,38 +1,21 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2017 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-plugin-host</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-
-<test-fixture id="basic">
-  <template>
-    <gr-js-api-interface></gr-js-api-interface>
-  </template>
-</test-fixture>
-
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import './gr-js-api-interface.js';
 import {BaseUrlBehavior} from '../../../behaviors/base-url-behavior/base-url-behavior.js';
 import {PRELOADED_PROTOCOL, PLUGIN_LOADING_TIMEOUT_MS} from './gr-api-utils.js';
@@ -41,6 +24,8 @@
 import {_testOnly_flushPreinstalls} from './gr-gerrit.js';
 import {_testOnly_initGerritPluginApi} from './gr-gerrit.js';
 
+const basicFixture = fixtureFromElement('gr-js-api-interface');
+
 const pluginApi = _testOnly_initGerritPluginApi();
 
 suite('gr-plugin-loader tests', () => {
@@ -64,7 +49,7 @@
     });
     pluginLoader = _testOnly_resetPluginLoader();
     sandbox.stub(document.body, 'appendChild');
-    fixture('basic');
+    basicFixture.instantiate();
     url = window.location.origin;
   });
 
@@ -502,6 +487,9 @@
   });
 
   suite('preloaded plugins', () => {
+    teardown(() => {
+      window.Gerrit._preloadedPlugins = null;
+    });
     test('skips preloaded plugins when load plugins', () => {
       const importHtmlPluginStub = sandbox.stub();
       sandbox.stub(pluginLoader, '_importHtmlPlugin', url => {
@@ -534,7 +522,6 @@
       assert.isTrue(
           pluginLoader.isPluginPreloaded(PRELOADED_PROTOCOL + 'baz')
       );
-      window.Gerrit._preloadedPlugins = null;
     });
 
     test('preloaded plugins are installed', () => {
@@ -555,4 +542,4 @@
     });
   });
 });
-</script>
+
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-rest-api_test.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-rest-api_test.js
index fcc3b669..69c8c44 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-rest-api_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-rest-api_test.js
@@ -1,31 +1,21 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2017 The Android Open Source Project
+/**
+ * @license
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<meta charset="utf-8">
-<title>gr-plugin-rest-api</title>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/components/wct-browser-legacy/browser.js"></script>
-<script type="module">
-import '../../../test/common-test-setup.js';
+import '../../../test/common-test-setup-karma.js';
 import './gr-js-api-interface.js';
 import {GrPluginRestApi} from './gr-plugin-rest-api.js';
 import {_testOnly_initGerritPluginApi} from './gr-gerrit.js';
@@ -157,4 +147,4 @@
     });
   });
 });
-</script>
+