cc: Recycle resources for software video decode.

When we update a compositor resource from a media::VideoFrame,
try to reuse resources from previous frames that were returned
to us by the ResourceProvider.

R=piman,enne
BUG=179729
Depends on: https://codereview.chromium.org/13445009/

Review URL: https://chromiumcodereview.appspot.com/13959005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@193409 0039d316-1c4b-4281-b951-d872f2087c98

cc/layers/video_layer_impl.cc

@@ -83,6 +83,9 @@ void VideoLayerImpl::WillDraw(ResourceProvider* resource_provider) {
   frame_ = provider_client_impl_->AcquireLockAndCurrentFrame();
 
   if (!frame_) {
+    // Drop any resources used by the updater if there is no frame to display.
+    updater_.reset();
+
     provider_client_impl_->ReleaseLock();
     return;
   }

cc/resources/video_resource_updater.h

@@ -10,7 +10,9 @@
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
 #include "cc/resources/texture_mailbox.h"
+#include "ui/gfx/size.h"
 
 namespace media {
 class SkCanvasVideoRenderer;
@@ -55,7 +57,8 @@ class VideoFrameExternalResources {
 
 // VideoResourceUpdater is by the video system to produce frame content as
 // resources consumable by the compositor.
-class VideoResourceUpdater {
+class VideoResourceUpdater
+    : public base::SupportsWeakPtr<VideoResourceUpdater> {
  public:
   explicit VideoResourceUpdater(ResourceProvider* resource_provider);
   ~VideoResourceUpdater();
@@ -68,8 +71,31 @@ class VideoResourceUpdater {
       const scoped_refptr<media::VideoFrame>& video_frame);
 
  private:
+  struct PlaneResource {
+    unsigned resource_id;
+    gfx::Size resource_size;
+    unsigned resource_format;
+    unsigned sync_point;
+
+    PlaneResource(unsigned resource_id,
+                  gfx::Size resource_size,
+                  unsigned resource_format,
+                  unsigned sync_point)
+        : resource_id(resource_id),
+          resource_size(resource_size),
+          resource_format(resource_format),
+          sync_point(sync_point) {}
+  };
+
   bool VerifyFrame(const scoped_refptr<media::VideoFrame>& video_frame);
 
+  static void RecycleResource(base::WeakPtr<VideoResourceUpdater> updater,
+                              ResourceProvider* resource_provider,
+                              unsigned resource_id,
+                              gfx::Size resource_size,
+                              unsigned resource_format,
+                              gpu::Mailbox mailbox,
+                              unsigned sync_point);
   static void ReturnTexture(ResourceProvider* resource_provider,
                             TextureMailbox::ReleaseCallback callback,
                             unsigned texture_id,
@@ -79,6 +105,8 @@ class VideoResourceUpdater {
   ResourceProvider* resource_provider_;
   scoped_ptr<media::SkCanvasVideoRenderer> video_renderer_;
 
+  std::vector<PlaneResource> recycled_resources_;
+
   DISALLOW_COPY_AND_ASSIGN(VideoResourceUpdater);
 };