Revert 190863 "Revert 190807 "Fix a Chrome renderer hang which o..."

> Revert 190807 "Fix a Chrome renderer hang which occurs when a We..."
> 
> > Fix a Chrome renderer hang which occurs when a WebMediaPlayerImpl instance is shutting down and hangs due to
> > a deadlock between the media pipeline thread and the Renderer main thread.
> > 
> > The media pipeline thread waits on a task(RendererGpuVideoDecoderFactories::AsyncCreateSharedMemory) to be
> > executed on the main thread while the main thread waits on the media pipeline thread to exit.
> > 
> > The proposed fix is to introduce the following functions on the media::GpuVideoDecoder::Factories interface.
> > 1. Abort:- Called during shutdown.
> > 2. IsAborted:- Called to check if shutdown is in progress.
> > 
> > The Abort function is called when the WebMediaPlayerImpl is shutting down. The video decoder factory sets an
> > event in this context. All tasks which complete asynchronously check for this event along with the event
> > which indicates that the async task completed. This ensures that they don't indefinitely wait during shutdown.
> > The asynchronous tasks in the RendererGpuVideoDecoderFactories now use a common event to signal completion
> > and return their results in member variables. This prevents a race between RendererGpuVideoDecoderFactories::Abort
> > being called and these tasks attempting to copy data to the callers stack which may have unwound at this point.
> > 
> > While debugging this problem, I also found that there are scenarios where the GVD::Reset never completes
> > thus hanging the renderer. This problem occurs when the GVD is in the kDrainingDecoder state, i.e. waiting
> > for a Flush to complete. The VRB is waiting for the GVD::Reset operation to complete. The VDA is waiting for
> > output picture buffers which the VRB is holding on to. Proposed fix for that was to flush out the ready frames
> > in the VRB::Flush call which unblocks the VDA.
> > 
> > I changed the ReadPixelsCB to take in a const SkBitmap& instead of void* to address the refcount issues with the
> > SkBitmap.
> > 
> > While running my test case with tip two DCHECK's in VideoFrameStream::OnDecoderStopped fired. The first one
> > is the case where the decoder is stopped while there is a pending read callback. The second one is for the same
> > scenario with a pending reset. These fire when the media pipeline is destroyed on the main renderer thread while
> > these operations are pending. I added code in the GpuVideoDecoder::Stop function to fire these callbacks which
> > seems like the right thing to do.
> > 
> > The other change in the GpuVideoDecoder::NotifyResetDone function was to remove the check for a NULL vda as there
> > are scenarios where in the decoder could be destroyed before this callback runs. We need to fire the read and
> > reset callbacks anyway.
> > 
> > BUG=179551
> > TEST=The rapid_video_change_test.html file added to media\test\data, when loaded in chrome should hang without
> > this patch. Needs some more work to get something similar running in the Chrome OS autotest suite.
> > Review URL: https://codereview.chromium.org/12634011
> 
> TBR=ananta@chromium.org
> Review URL: https://codereview.chromium.org/12942011

TBR=ygorshenin@chromium.org
Review URL: https://codereview.chromium.org/13044009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@190912 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 9 insertions, 0 deletions

diff --git a/webkit/media/webmediaplayer_impl.cc b/webkit/media/webmediaplayer_impl.cc
index 0b76985..4008ffc 100644
--- a/webkit/media/webmediaplayer_impl.cc
+++ b/webkit/media/webmediaplayer_impl.cc
@@ -188,6 +188,7 @@ WebMediaPlayerImpl::WebMediaPlayerImpl(
         new media::GpuVideoDecoder(
             media_thread_.message_loop_proxy(),
             params.gpu_factories()));
+    gpu_factories_ = params.gpu_factories();
   }
 
   // Create default video renderer.
@@ -1156,6 +1157,11 @@ void WebMediaPlayerImpl::Destroy() {
   if (chunk_demuxer_)
     chunk_demuxer_->Shutdown();
 
+  if (gpu_factories_) {
+    gpu_factories_->Abort();
+    gpu_factories_ = NULL;
+  }
+
   // Make sure to kill the pipeline so there's no more media threads running.
   // Note: stopping the pipeline might block for a long time.
   base::WaitableEvent waiter(false, false);
diff --git a/webkit/media/webmediaplayer_impl.h b/webkit/media/webmediaplayer_impl.h
index 3e1799a..68e6f3c 100644
--- a/webkit/media/webmediaplayer_impl.h
+++ b/webkit/media/webmediaplayer_impl.h
@@ -31,6 +31,7 @@
 #include "media/base/audio_renderer_sink.h"
 #include "media/base/decryptor.h"
 #include "media/base/pipeline.h"
+#include "media/filters/gpu_video_decoder.h"
 #include "media/filters/skcanvas_video_renderer.h"
 #include "skia/ext/platform_canvas.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebGraphicsContext3D.h"
@@ -359,6 +360,8 @@ class WebMediaPlayerImpl
   // not NULL while the compositor is actively using this webmediaplayer.
   cc::VideoFrameProvider::Client* video_frame_provider_client_;
 
+  scoped_refptr<media::GpuVideoDecoder::Factories> gpu_factories_;
+
   DISALLOW_COPY_AND_ASSIGN(WebMediaPlayerImpl);
 };