Fix fullscreen video race condition.

content/renderer/media/android/renderer_media_player_manager.cc

Index: content/renderer/media/android/renderer_media_player_manager.cc
diff --git a/content/renderer/media/android/renderer_media_player_manager.cc b/content/renderer/media/android/renderer_media_player_manager.cc
index 6969511946544753df6229b653dbd617b63b2766..fbfc380d3ac56d13418d276deeeea88f6476694f 100644
--- a/content/renderer/media/android/renderer_media_player_manager.cc
+++ b/content/renderer/media/android/renderer_media_player_manager.cc
@@ -24,7 +24,8 @@ namespace content {
 RendererMediaPlayerManager::RendererMediaPlayerManager(RenderView* render_view)
     : RenderViewObserver(render_view),
       next_media_player_id_(0),
-      fullscreen_frame_(NULL) {}
+      fullscreen_frame_(NULL),
+      pending_fullscreen_frame_(NULL) {}
 
 RendererMediaPlayerManager::~RendererMediaPlayerManager() {
   std::map<int, WebMediaPlayerAndroid*>::iterator player_it;
@@ -223,7 +224,9 @@ void RendererMediaPlayerManager::OnRequestFullscreen(int player_id) {
     player->OnRequestFullscreen();
 }
 
-void RendererMediaPlayerManager::EnterFullscreen(int player_id) {
+void RendererMediaPlayerManager::EnterFullscreen(int player_id,
+                                                 blink::WebFrame* frame) {
+  pending_fullscreen_frame_ = frame;
   Send(new MediaPlayerHostMsg_EnterFullscreen(routing_id(), player_id));
 }
 
@@ -385,6 +388,7 @@ bool RendererMediaPlayerManager::CanEnterFullscreen(blink::WebFrame* frame) {
 }
 
 void RendererMediaPlayerManager::DidEnterFullscreen(blink::WebFrame* frame) {
+  pending_fullscreen_frame_ = NULL;

[qinmin, 2014/01/28 17:41:34]

what if ExitFullscreen() is called before this call? Since
pending_fullscreen_frame_ is non-null, if another video element calls
RequestFullscreen(), it wouldn't be able to do so immediately after we fix
CanEnterFullscreen().

   fullscreen_frame_ = frame;
 }
 
@@ -396,6 +400,10 @@ bool RendererMediaPlayerManager::IsInFullscreen(blink::WebFrame* frame) {
   return fullscreen_frame_ == frame;
 }
 
+bool RendererMediaPlayerManager::ShouldEnterFullscreen(blink::WebFrame* frame) {

[qinmin, 2014/01/28 17:41:34]

This logic is also needed for CanEnterFullscreen(), I think we should merge
these two functions.

+  return fullscreen_frame_ == frame || pending_fullscreen_frame_ == frame;
+}
+
 #if defined(VIDEO_HOLE)
 void RendererMediaPlayerManager::RequestExternalSurface(
     int player_id,