Ensure fullscreen mode is exited for same-site navigations.

content/browser/web_contents/web_contents_impl.cc

 // 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.
 
 #include "content/browser/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 2215 matching lines @@
       WebContentsObserver,
       observers_,
       DidCommitProvisionalLoadForFrame(render_frame_id,
                                        frame_unique_name,
                                        is_main_frame,
                                        url,
                                        transition_type,
                                        render_view_host));
 }
 
+void WebContentsImpl::DidNavigateMainFramePreCommit(
+    const FrameHostMsg_DidCommitProvisionalLoad_Params& params) {
+  // Ensure fullscreen mode is exited before committing the navigation to a
+  // different page.  The next page will not start out assuming it is in
+  // fullscreen mode.
+  if (params.was_within_same_page) {
+    // No document change?  Then, the renderer shall decide whether to exit
+    // fullscreen.
+    return;
+  }
+  RenderViewHost* const old_render_view_host = GetRenderViewHost();
+  if (old_render_view_host && IsFullscreenForCurrentTab())
+    old_render_view_host->ExitFullscreen();

[Charlie Reis, 2014/04/01 23:12:38]

GetRenderViewHost() will never return null in this context (since we're hearing
an IPC reply and thus have initialized it), so you can just call it here rather
than storing it in old_render_view_host.

[miu, 2014/04/01 23:39:35]

Done.

+  DCHECK(!IsFullscreenForCurrentTab());
+  // TODO(creis): How to handle subframes that go fullscreen?

[Charlie Reis, 2014/04/01 23:12:38]

You may know the answer to this, actually.  Can subframes go fullscreen, or is
this a moot point?  If not, we can remove the TODO.

[miu, 2014/04/01 23:39:35]

Removed TODO.  I just looked at the W3C spec, and it looks like any subdocument
entering fullscreen mode should bubble up the request to ancestor documents.  I
interpret this as "a subframe entering fullscreen will cause the main frame to
enter fullscreen."

+}
+
 void WebContentsImpl::DidNavigateMainFramePostCommit(
     const LoadCommittedDetails& details,
     const FrameHostMsg_DidCommitProvisionalLoad_Params& params) {
   if (details.is_navigation_to_different_page()) {
     // Clear the status bubble. This is a workaround for a bug where WebKit
     // doesn't let us know that the cursor left an element during a
     // transition (this is also why the mouse cursor remains as a hand after
     // clicking on a link); see bugs 1184641 and 980803. We don't want to
     // clear the bubble when a user navigates to a named anchor in the same
     // page.
@@ skipping 795 matching lines @@
     return;
   }
 #endif
 
   // Ignore this if it comes from a RenderViewHost that we aren't showing.
   if (delegate_ && rvh == GetRenderViewHost())
     delegate_->CloseContents(this);
 }
 
 void WebContentsImpl::SwappedOut(RenderFrameHost* rfh) {
-  // TODO(creis): Handle subframes that go fullscreen.
-  if (rfh->GetRenderViewHost() == GetRenderViewHost()) {
-    // Exit fullscreen mode before the current RVH is swapped out.  For numerous
-    // cases, there is no guarantee the renderer would/could initiate an exit.
-    // Example: http://crbug.com/347232
-    if (IsFullscreenForCurrentTab()) {
-      rfh->GetRenderViewHost()->ExitFullscreen();
-      DCHECK(!IsFullscreenForCurrentTab());
-    }
-
-    if (delegate_)
-      delegate_->SwappedOut(this);
-  }
+  if (delegate_ && rfh->GetRenderViewHost() == GetRenderViewHost())
+    delegate_->SwappedOut(this);
 }
 
 void WebContentsImpl::RequestMove(const gfx::Rect& new_bounds) {
   if (delegate_ && delegate_->IsPopupOrPanel(this))
     delegate_->MoveContents(this, new_bounds);
 }
 
 void WebContentsImpl::DidStartLoading(RenderFrameHost* render_frame_host,
                                       bool to_different_document) {
   SetIsLoading(render_frame_host->GetRenderViewHost(), true,
@@ skipping 596 matching lines @@
 
 void WebContentsImpl::OnPreferredSizeChanged(const gfx::Size& old_size) {
   if (!delegate_)
     return;
   const gfx::Size new_size = GetPreferredSize();
   if (new_size != old_size)
     delegate_->UpdatePreferredSize(this, new_size);
 }
 
 }  // namespace content