JavaScript dialogs cause a page to lose fullscreen.

content/browser/web_contents/web_contents_impl.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_IMPL_H_
 #define CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_IMPL_H_
 
 #include <stdint.h>
 
 #include <functional>
@@ skipping 430 matching lines @@
                     uint32_t max_bitmap_size,
                     bool bypass_cache,
                     const ImageDownloadCallback& callback) override;
   bool IsSubframe() const override;
   void Find(int request_id,
             const base::string16& search_text,
             const blink::WebFindOptions& options) override;
   void StopFinding(StopFindAction action) override;
   bool WasRecentlyAudible() override;
   void GetManifest(const GetManifestCallback& callback) override;
+  bool IsFullscreenForCurrentTab() const override;
   void ExitFullscreen(bool will_cause_resize) override;
   void ResumeLoadingCreatedWebContents() override;
   void OnPasswordInputShownOnHttp() override;
   void OnAllPasswordInputsHiddenOnHttp() override;
   void OnCreditCardInputShownOnHttp() override;
   void SetIsOverlayContent(bool is_overlay_content) override;
   bool IsFocusedElementEditable() override;
   void ClearFocusedElement() override;
   bool IsShowingContextMenu() const override;
   void SetShowingContextMenu(bool showing) override;
@@ skipping 237 matching lines @@
       RenderWidgetHostImpl* receiving_widget) override;
   RenderWidgetHostImpl* GetRenderWidgetHostWithPageFocus() override;
   void FocusOwningWebContents(
       RenderWidgetHostImpl* render_widget_host) override;
   void RendererUnresponsive(RenderWidgetHostImpl* render_widget_host) override;
   void RendererResponsive(RenderWidgetHostImpl* render_widget_host) override;
   void RequestToLockMouse(RenderWidgetHostImpl* render_widget_host,
                           bool user_gesture,
                           bool last_unlocked_by_target,
                           bool privileged) override;
-  bool IsFullscreenForCurrentTab() const override;
+  // The following function is already listed under WebContents overrides:
+  // bool IsFullscreenForCurrentTab() const override;

[Matt Giuca, 2017/06/09 06:16:37]

Shouldn't have commented-out lines of code.

How about just "// IsFullscreenForCurrentTab is already ...."

[Avi (use Gerrit), 2017/06/09 14:36:23]

This is paralleling lines 689, etc, above.

   blink::WebDisplayMode GetDisplayMode(
       RenderWidgetHostImpl* render_widget_host) const override;
   void LostCapture(RenderWidgetHostImpl* render_widget_host) override;
   void LostMouseLock(RenderWidgetHostImpl* render_widget_host) override;
   bool HasMouseLock(RenderWidgetHostImpl* render_widget_host) override;
   RenderWidgetHostImpl* GetMouseLockWidget() override;
   void OnRenderFrameProxyVisibilityChanged(bool visible) override;
   void SendScreenRects() override;
   TextInputManager* GetTextInputManager() override;
   bool OnUpdateDragCursor() override;
@@ skipping 180 matching lines @@
   FRIEND_TEST_ALL_PREFIXES(RenderFrameHostManagerTest, PageDoesBackAndReload);
   FRIEND_TEST_ALL_PREFIXES(SitePerProcessBrowserTest, CrossSiteIframe);
   FRIEND_TEST_ALL_PREFIXES(SitePerProcessBrowserTest,
                            TwoSubframesCreatePopupsSimultaneously);
   FRIEND_TEST_ALL_PREFIXES(SitePerProcessBrowserTest,
                            TwoSubframesCreatePopupMenuWidgetsSimultaneously);
   FRIEND_TEST_ALL_PREFIXES(SitePerProcessAccessibilityBrowserTest,
                            CrossSiteIframeAccessibility);
   FRIEND_TEST_ALL_PREFIXES(WebContentsImplBrowserTest,
                            JavaScriptDialogsInMainAndSubframes);
+  FRIEND_TEST_ALL_PREFIXES(WebContentsImplBrowserTest,
+                           DialogsFromJavaScriptEndFullscreen);
   FRIEND_TEST_ALL_PREFIXES(RenderFrameHostImplBrowserTest,
                            IframeBeforeUnloadParentHang);
   FRIEND_TEST_ALL_PREFIXES(RenderFrameHostImplBrowserTest,
                            BeforeUnloadDialogRequiresGesture);
 
   // So |find_request_manager_| can be accessed for testing.
   friend class FindRequestManagerTest;
 
   // TODO(brettw) TestWebContents shouldn't exist!
   friend class TestWebContents;
@@ skipping 716 matching lines @@
   // Adds/removes a callback called on creation of each new WebContents.
   static void AddCreatedCallbackForTesting(const CreatedCallback& callback);
   static void RemoveCreatedCallbackForTesting(const CreatedCallback& callback);
 
   DISALLOW_COPY_AND_ASSIGN(FriendWrapper);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_IMPL_H_