Update sinon version

The WCT tests used deprecated version on sinon. This change adds
the newest version of sinon to polygerrit and update tests.

Change-Id: Ic746c4afc97779974da643362e17c9c1bb1cbf48
diff --git a/polygerrit-ui/app/elements/admin/gr-group/gr-group_test.js b/polygerrit-ui/app/elements/admin/gr-group/gr-group_test.js
index 0cb5dfe..c6054b2 100644
--- a/polygerrit-ui/app/elements/admin/gr-group/gr-group_test.js
+++ b/polygerrit-ui/app/elements/admin/gr-group/gr-group_test.js
@@ -22,7 +22,7 @@
 
 suite('gr-group tests', () => {
   let element;
-  let sandbox;
+
   let groupStub;
   const group = {
     id: '6a1e70e1a88782771a91808c8af9bbb7a9871389',
@@ -36,20 +36,14 @@
   };
 
   setup(() => {
-    sandbox = sinon.sandbox.create();
     stub('gr-rest-api-interface', {
       getLoggedIn() { return Promise.resolve(true); },
     });
     element = basicFixture.instantiate();
-    groupStub = sandbox.stub(
+    groupStub = sinon.stub(
         element.$.restAPI,
-        'getGroupConfig',
-        () => Promise.resolve(group)
-    );
-  });
-
-  teardown(() => {
-    sandbox.restore();
+        'getGroupConfig')
+        .callsFake(() => Promise.resolve(group));
   });
 
   test('loading displays before group config is loaded', () => {
@@ -61,10 +55,10 @@
   });
 
   test('default values are populated with internal group', done => {
-    sandbox.stub(
+    sinon.stub(
         element.$.restAPI,
-        'getIsGroupOwner',
-        () => Promise.resolve(true));
+        'getIsGroupOwner')
+        .callsFake(() => Promise.resolve(true));
     element.groupId = 1;
     element._loadGroup().then(() => {
       assert.isTrue(element._groupIsInternal);
@@ -77,14 +71,14 @@
     const groupExternal = Object.assign({}, group);
     groupExternal.id = 'external-group-id';
     groupStub.restore();
-    groupStub = sandbox.stub(
+    groupStub = sinon.stub(
         element.$.restAPI,
-        'getGroupConfig',
-        () => Promise.resolve(groupExternal));
-    sandbox.stub(
+        'getGroupConfig')
+        .callsFake(() => Promise.resolve(groupExternal));
+    sinon.stub(
         element.$.restAPI,
-        'getIsGroupOwner',
-        () => Promise.resolve(true));
+        'getIsGroupOwner')
+        .callsFake(() => Promise.resolve(true));
     element.groupId = 1;
     element._loadGroup().then(() => {
       assert.isFalse(element._groupIsInternal);
@@ -102,15 +96,15 @@
     };
     element._groupName = groupName;
 
-    sandbox.stub(
+    sinon.stub(
         element.$.restAPI,
-        'getIsGroupOwner',
-        () => Promise.resolve(true));
+        'getIsGroupOwner')
+        .callsFake(() => Promise.resolve(true));
 
-    sandbox.stub(
+    sinon.stub(
         element.$.restAPI,
-        'saveGroupName',
-        () => Promise.resolve({status: 200}));
+        'saveGroupName')
+        .callsFake(() => Promise.resolve({status: 200}));
 
     const button = element.$.inputUpdateNameBtn;
 
@@ -141,10 +135,10 @@
     element._groupConfigOwner = 'testId';
     element._groupOwner = true;
 
-    sandbox.stub(
+    sinon.stub(
         element.$.restAPI,
-        'getIsGroupOwner',
-        () => Promise.resolve({status: 200}));
+        'getIsGroupOwner')
+        .callsFake(() => Promise.resolve({status: 200}));
 
     const button = element.$.inputUpdateOwnerBtn;
 
@@ -168,10 +162,10 @@
   test('test for undefined group name', done => {
     groupStub.restore();
 
-    sandbox.stub(
+    sinon.stub(
         element.$.restAPI,
-        'getGroupConfig',
-        () => Promise.resolve({}));
+        'getGroupConfig')
+        .callsFake(() => Promise.resolve({}));
 
     assert.isUndefined(element.groupId);
 
@@ -195,10 +189,10 @@
       name: 'test-group',
     };
 
-    sandbox.stub(element.$.restAPI, 'saveGroupName')
+    sinon.stub(element.$.restAPI, 'saveGroupName')
         .returns(Promise.resolve({status: 200}));
 
-    const showStub = sandbox.stub(element, 'dispatchEvent');
+    const showStub = sinon.stub(element, 'dispatchEvent');
     element._handleSaveName()
         .then(() => {
           assert.isTrue(showStub.called);
@@ -245,10 +239,10 @@
     element.groupId = 1;
 
     const response = {status: 404};
-    sandbox.stub(
-        element.$.restAPI, 'getGroupConfig', (group, errFn) => {
-          errFn(response);
-        });
+    sinon.stub(
+        element.$.restAPI, 'getGroupConfig').callsFake((group, errFn) => {
+      errFn(response);
+    });
 
     element.addEventListener('page-error', e => {
       assert.deepEqual(e.detail.response, response);