Complete cleanup of overlayOpen class

Change 349418 removed the css rule that was reading the class, hence
we can remove setting the class as well.

Release-Notes: skip
Google-bug-id: b/255524908
Change-Id: I5a6e0d3cf55befad5102fbd072c0328845578bbe
diff --git a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
index 007dd15..aa85a7f 100644
--- a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
+++ b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
@@ -593,18 +593,6 @@
   }
 
   private setupListeners() {
-    this.addEventListener(
-      // When an overlay is opened in a mobile viewport, the overlay has a full
-      // screen view. When it has a full screen view, we do not want the
-      // background to be scrollable. This will eliminate background scroll by
-      // hiding most of the contents on the screen upon opening, and showing
-      // again upon closing.
-      'fullscreen-overlay-opened',
-      () => this.handleHideBackgroundContent()
-    );
-    this.addEventListener('fullscreen-overlay-closed', () =>
-      this.handleShowBackgroundContent()
-    );
     this.addEventListener('open-reply-dialog', () => this.openReplyDialog());
     this.addEventListener('change-message-deleted', () => fireReload(this));
     this.addEventListener('editable-content-save', e =>
@@ -2026,18 +2014,6 @@
   }
 
   // Private but used in tests.
-  handleHideBackgroundContent() {
-    assertIsDefined(this.mainContent);
-    this.mainContent.classList.add('overlayOpen');
-  }
-
-  // Private but used in tests.
-  handleShowBackgroundContent() {
-    assertIsDefined(this.mainContent);
-    this.mainContent.classList.remove('overlayOpen');
-  }
-
-  // Private but used in tests.
   handleReplySent() {
     this.addEventListener(
       'change-details-loaded',
diff --git a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view_test.ts b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view_test.ts
index 301e44b..6749401 100644
--- a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view_test.ts
+++ b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view_test.ts
@@ -12,7 +12,6 @@
   CommentSide,
   DefaultBase,
   DiffViewMode,
-  HttpMethod,
   MessageTag,
   createDefaultPreferences,
   Tab,
@@ -91,7 +90,6 @@
   LoadingStatus,
 } from '../../../models/change/change-model';
 import {FocusTarget, GrReplyDialog} from '../gr-reply-dialog/gr-reply-dialog';
-import {GrOverlay} from '../../shared/gr-overlay/gr-overlay';
 import {GrChangeStar} from '../../shared/gr-change-star/gr-change-star';
 import {GrThreadList} from '../gr-thread-list/gr-thread-list';
 import {assertIsDefined} from '../../../utils/common-util';
@@ -859,68 +857,6 @@
       assert.equal(openSpy.callCount, 1);
     });
 
-    test('fullscreen-overlay-opened hides content', async () => {
-      element.loggedIn = true;
-      element.loading = false;
-      element.change = {
-        ...createChangeViewChange(),
-        labels: {},
-        actions: {
-          abandon: {
-            enabled: true,
-            label: 'Abandon',
-            method: HttpMethod.POST,
-            title: 'Abandon',
-          },
-        },
-      };
-      await element.updateComplete;
-      const handlerSpy = sinon.spy(element, 'handleHideBackgroundContent');
-      const overlay = queryAndAssert<GrOverlay>(element, '#replyOverlay');
-      overlay.dispatchEvent(
-        new CustomEvent('fullscreen-overlay-opened', {
-          composed: true,
-          bubbles: true,
-        })
-      );
-      await element.updateComplete;
-      assert.isTrue(handlerSpy.called);
-      assertIsDefined(element.mainContent);
-      assertIsDefined(element.actions);
-      assert.isTrue(element.mainContent.classList.contains('overlayOpen'));
-      assert.equal(getComputedStyle(element.actions).display, 'flex');
-    });
-
-    test('fullscreen-overlay-closed shows content', async () => {
-      element.loggedIn = true;
-      element.loading = false;
-      element.change = {
-        ...createChangeViewChange(),
-        labels: {},
-        actions: {
-          abandon: {
-            enabled: true,
-            label: 'Abandon',
-            method: HttpMethod.POST,
-            title: 'Abandon',
-          },
-        },
-      };
-      await element.updateComplete;
-      const handlerSpy = sinon.spy(element, 'handleShowBackgroundContent');
-      const overlay = queryAndAssert<GrOverlay>(element, '#replyOverlay');
-      overlay.dispatchEvent(
-        new CustomEvent('fullscreen-overlay-closed', {
-          composed: true,
-          bubbles: true,
-        })
-      );
-      await element.updateComplete;
-      assert.isTrue(handlerSpy.called);
-      assertIsDefined(element.mainContent);
-      assert.isFalse(element.mainContent.classList.contains('overlayOpen'));
-    });
-
     test('expand all messages when expand-diffs fired', () => {
       assertIsDefined(element.fileList);
       assertIsDefined(element.fileListHeader);