Replace at-/de-tached with dis-connectedCallback

attached() and detached() are Polymer 1 legacy.

Change-Id: Ic86d07bfb95ec316880db261a913004f5a6e5a22
diff --git a/polygerrit-ui/app/elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog.ts b/polygerrit-ui/app/elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog.ts
index 24f34a6..c95f87d 100644
--- a/polygerrit-ui/app/elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog.ts
+++ b/polygerrit-ui/app/elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog.ts
@@ -131,8 +131,8 @@
     });
   }
 
-  attached() {
-    super.attached();
+  connectedCallback() {
+    super.connectedCallback();
     this.refitOverlay = () => {
       // re-center the dialog as content changed
       fireEvent(this.$.applyFixOverlay, 'iron-resize');
@@ -140,11 +140,11 @@
     this.addEventListener('diff-context-expanded', this.refitOverlay);
   }
 
-  detached() {
-    super.detached();
+  disconnectedCallback() {
     if (this.refitOverlay) {
       this.removeEventListener('diff-context-expanded', this.refitOverlay);
     }
+    super.disconnectedCallback();
   }
 
   _showSelectedFixSuggestion(fixSuggestion: FixSuggestionInfo) {
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-element.ts b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-element.ts
index 25aac8d..ae82036 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-element.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-element.ts
@@ -161,11 +161,11 @@
   _cancelableRenderPromise: CancelablePromise<unknown> | null = null;
 
   /** @override */
-  detached() {
-    super.detached();
+  disconnectedCallback() {
     if (this._builder) {
       this._builder.clear();
     }
+    super.disconnectedCallback();
   }
 
   get diffElement() {
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor.ts b/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor.ts
index a19968c..35df51a 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor.ts
@@ -128,8 +128,8 @@
 
   /** @override */
   disconnectedCallback() {
-    super.disconnectedCallback();
     window.removeEventListener('scroll', this._boundHandleWindowScroll);
+    super.disconnectedCallback();
   }
 
   // Don't remove - used by clients embedding gr-diff outside of Gerrit.
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.ts b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.ts
index 0f53a26..fb28e2b 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.ts
@@ -88,8 +88,9 @@
   }
 
   /** @override */
-  detached() {
+  disconnectedCallback() {
     this.cancelDebouncer(DEBOUNCER_SELECTION_CHANGE);
+    super.disconnectedCallback();
   }
 
   get diffBuilder() {
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.ts b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.ts
index e6f08b01..d40a8a6 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.ts
@@ -307,17 +307,17 @@
   }
 
   /** @override */
-  attached() {
-    super.attached();
+  connectedCallback() {
+    super.connectedCallback();
     this._getLoggedIn().then(loggedIn => {
       this._loggedIn = loggedIn;
     });
   }
 
   /** @override */
-  detached() {
-    super.detached();
+  disconnectedCallback() {
     this.clear();
+    super.disconnectedCallback();
   }
 
   initLayers() {
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.js b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.js
index 3d6383b..267ca5f 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.js
@@ -970,7 +970,7 @@
   suite('create-comment', () => {
     setup(async () => {
       loggedIn = true;
-      element.attached();
+      element.connectedCallback();
       await flush();
     });
 
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector.ts b/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector.ts
index 0a22556..cc7bb98 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector.ts
@@ -45,7 +45,9 @@
 
   private readonly restApiService = appContext.restApiService;
 
-  attached() {
+  /** @override */
+  connectedCallback() {
+    super.connectedCallback();
     ((IronA11yAnnouncer as unknown) as FixIronA11yAnnouncer).requestAvailability();
   }
 
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor.ts b/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor.ts
index f4772e3..c13092f 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor.ts
@@ -114,17 +114,17 @@
   _isScrolling?: boolean;
 
   /** @override */
-  attached() {
-    super.attached();
+  connectedCallback() {
+    super.connectedCallback();
     this.listen(window, 'scroll', '_handleWindowScroll');
   }
 
   /** @override */
-  detached() {
-    super.detached();
+  disconnectedCallback() {
     this.cancelDebouncer(DEBOUNCER_RESET_IS_SCROLLING);
     this.cancel();
     this.unlisten(window, 'scroll', '_handleWindowScroll');
+    super.disconnectedCallback();
   }
 
   _handleWindowScroll() {
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor_test.js b/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor_test.js
index b8f7498..5ecc962 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor_test.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor_test.js
@@ -1113,7 +1113,7 @@
   test('detaching cancels', () => {
     element = basicFixture.instantiate();
     sinon.stub(element, 'cancel');
-    element.detached();
+    element.disconnectedCallback();
     assert(element.cancel.called);
   });
 });
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection.ts b/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection.ts
index 39acb86..cee5ef6 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection.ts
@@ -74,8 +74,8 @@
   }
 
   /** @override */
-  attached() {
-    super.attached();
+  connectedCallback() {
+    super.connectedCallback();
     this.classList.add(SelectionClass.RIGHT);
   }
 
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.ts b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.ts
index d8dbb49..e94cd23 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.ts
@@ -325,11 +325,6 @@
     this._throttledToggleFileReviewed = this._throttleWrap(e =>
       this._handleToggleFileReviewed(e as CustomKeyboardEvent)
     );
-  }
-
-  /** @override */
-  attached() {
-    super.attached();
     this._getLoggedIn().then(loggedIn => {
       this._loggedIn = loggedIn;
     });
@@ -343,10 +338,11 @@
   }
 
   /** @override */
-  detached() {
+  disconnectedCallback() {
     if (this._onRenderHandler) {
       this.$.diffHost.removeEventListener('render', this._onRenderHandler);
     }
+    super.disconnectedCallback();
   }
 
   _getLoggedIn() {
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.ts b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.ts
index 802397b..2e97765 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.ts
@@ -295,17 +295,17 @@
   }
 
   /** @override */
-  attached() {
-    super.attached();
+  connectedCallback() {
+    super.connectedCallback();
     this._observeNodes();
   }
 
   /** @override */
-  detached() {
+  disconnectedCallback() {
     this.cancelDebouncer(RENDER_DIFF_TABLE_DEBOUNCE_NAME);
-    super.detached();
     this._unobserveIncrementalNodes();
     this._unobserveNodes();
+    super.disconnectedCallback();
   }
 
   showNoChangeMessage(