Allow out-of-process iframes to render to compositing surfaces.

content/renderer/child_frame_compositing_helper.h

Index: content/renderer/child_frame_compositing_helper.h
diff --git a/content/renderer/child_frame_compositing_helper.h b/content/renderer/child_frame_compositing_helper.h
index 0700d9cc24f6f57195c730be6e1a0225ececae59..47bb33ff93cb118327af52f3d581d98b8d90876a 100644
--- a/content/renderer/child_frame_compositing_helper.h
+++ b/content/renderer/child_frame_compositing_helper.h
@@ -20,9 +20,13 @@ class SharedMemory;
 }
 
 namespace cc {
+struct SurfaceId;
+struct SurfaceSequence;
+
 class CompositorFrame;
 class Layer;
 class SolidColorLayer;
+class SurfaceLayer;
 class DelegatedFrameProvider;
 class DelegatedFrameResourceCollection;
 class DelegatedRendererLayer;
@@ -66,6 +70,10 @@ class CONTENT_EXPORT ChildFrameCompositingHelper
                                 uint32 output_surface_id,
                                 int host_id,
                                 base::SharedMemoryHandle handle);
+  void OnSetSurface(const cc::SurfaceId& surface_id,
+                    const gfx::Size& frame_size,
+                    float scale_factor,
+                    const cc::SurfaceSequence& sequence);
   void UpdateVisibility(bool);
   void ChildFrameGone();
 
@@ -98,6 +106,11 @@ class CONTENT_EXPORT ChildFrameCompositingHelper
                                          float device_scale_factor,
                                          cc::Layer* layer);
   void SendReturnedDelegatedResources();
+  static void SatisfyCallback(ChildFrameCompositingHelper* helper,
+                              cc::SurfaceSequence sequence);

[dcheng, 2015/05/28 22:16:30]

Is there a convention for whether this is passed by value or reference?

[kenrb, 2015/05/29 19:29:37]

It has to match the base::Callback definitions in surface_layer.h.

+  static void RequireCallback(ChildFrameCompositingHelper* helper,
+                              cc::SurfaceId id,
+                              cc::SurfaceSequence sequence);
 
   int host_routing_id_;
   int last_route_id_;
@@ -117,6 +130,9 @@ class CONTENT_EXPORT ChildFrameCompositingHelper
   scoped_refptr<cc::DelegatedFrameResourceCollection> resource_collection_;
   scoped_refptr<cc::DelegatedFrameProvider> frame_provider_;
 
+  // For cc::Surface support.
+  scoped_refptr<cc::SurfaceLayer> surface_layer_;
+
   scoped_refptr<cc::SolidColorLayer> background_layer_;
   scoped_refptr<cc::DelegatedRendererLayer> delegated_layer_;
   scoped_ptr<blink::WebLayer> web_layer_;