aura: Clean up compositor initialization/destruction.

content/common/gpu/client/gl_helper.cc

Index: content/common/gpu/client/gl_helper.cc
diff --git a/content/common/gpu/client/gl_helper.cc b/content/common/gpu/client/gl_helper.cc
index e8afdd1da9a740bd5107a6c658d54a58ba1e3fe6..0a10d4aa7e5229e1b18ac1b369ad52bdf29aeb3d 100644
--- a/content/common/gpu/client/gl_helper.cc
+++ b/content/common/gpu/client/gl_helper.cc
@@ -154,7 +154,7 @@ class GLHelper::CopyTextureToImpl :
       const base::Callback<void(bool)>& callback);
 
   void ReadbackPlane(TextureFrameBufferPair* source,
-                     media::VideoFrame* target,
+                     const scoped_refptr<media::VideoFrame>& target,
                      int plane,
                      int size_shift,
                      const gfx::Rect& dst_subrect,
@@ -232,7 +232,7 @@ class GLHelper::CopyTextureToImpl :
     virtual void ReadbackYUV(
         const gpu::Mailbox& mailbox,
         uint32 sync_point,
-        media::VideoFrame* target,
+        const scoped_refptr<media::VideoFrame>& target,
         const base::Callback<void(bool)>& callback) OVERRIDE;
 
     virtual ScalerInterface* scaler() OVERRIDE {
@@ -270,7 +270,7 @@ class GLHelper::CopyTextureToImpl :
     virtual void ReadbackYUV(
         const gpu::Mailbox& mailbox,
         uint32 sync_point,
-        media::VideoFrame* target,
+        const scoped_refptr<media::VideoFrame>& target,
         const base::Callback<void(bool)>& callback) OVERRIDE;
 
     virtual ScalerInterface* scaler() OVERRIDE {
@@ -729,7 +729,7 @@ void GLHelper::CopyTextureFullImage(WebKit::WebGLId texture,
 
 void GLHelper::CopyTextureToImpl::ReadbackPlane(
     TextureFrameBufferPair* source,
-    media::VideoFrame* target,
+    const scoped_refptr<media::VideoFrame>& target,
     int plane,
     int size_shift,
     const gfx::Rect& dst_subrect,
@@ -813,11 +813,17 @@ GLHelper::CopyTextureToImpl::ReadbackYUVImpl::ReadbackYUVImpl(
   DCHECK(!(dst_subrect.y() & 1));
 }
 
+static void CallbackKeepingVideoFrameAlive(
+    scoped_refptr<media::VideoFrame> video_frame,
+    const base::Callback<void(bool)>& callback,
+    bool success) {
+  callback.Run(success);
+}
 
 void GLHelper::CopyTextureToImpl::ReadbackYUVImpl::ReadbackYUV(
     const gpu::Mailbox& mailbox,
     uint32 sync_point,
-    media::VideoFrame *target,
+    const scoped_refptr<media::VideoFrame>& target,
     const base::Callback<void(bool)>& callback) {
   WebGLId mailbox_texture =
       copy_impl_->ConsumeMailboxToTexture(mailbox, sync_point);
@@ -838,7 +844,8 @@ void GLHelper::CopyTextureToImpl::ReadbackYUVImpl::ReadbackYUV(
     return;
   }
 
-  // Read back planes, one at a time.
+  // Read back planes, one at a time. Keep the video frame alive while doing the
+  // readback.
   copy_impl_->ReadbackPlane(y_.texture_and_framebuffer(),
                             target,
                             media::VideoFrame::kYPlane,
@@ -856,7 +863,9 @@ void GLHelper::CopyTextureToImpl::ReadbackYUVImpl::ReadbackYUV(
                             media::VideoFrame::kVPlane,
                             1,
                             dst_subrect_,
-                            callback);
+                            base::Bind(&CallbackKeepingVideoFrameAlive,
+                                       target,
+                                       callback));
   context_->bindFramebuffer(GL_FRAMEBUFFER, 0);
   media::LetterboxYUV(target, dst_subrect_);
 }
@@ -933,7 +942,7 @@ GLHelper::CopyTextureToImpl::ReadbackYUV_MRT::ReadbackYUV_MRT(
 void GLHelper::CopyTextureToImpl::ReadbackYUV_MRT::ReadbackYUV(
     const gpu::Mailbox& mailbox,
     uint32 sync_point,
-    media::VideoFrame *target,
+    const scoped_refptr<media::VideoFrame>& target,
     const base::Callback<void(bool)>& callback) {
   WebGLId mailbox_texture =
       copy_impl_->ConsumeMailboxToTexture(mailbox, sync_point);
@@ -976,7 +985,9 @@ void GLHelper::CopyTextureToImpl::ReadbackYUV_MRT::ReadbackYUV(
                             media::VideoFrame::kVPlane,
                             1,
                             dst_subrect_,
-                            callback);
+                            base::Bind(&CallbackKeepingVideoFrameAlive,
+                                       target,
+                                       callback));
   context_->bindFramebuffer(GL_FRAMEBUFFER, 0);
   media::LetterboxYUV(target, dst_subrect_);
 }