WIP: Propagate SurfaceID up window tree hierarchy

services/ui/surfaces/compositor_frame_sink.h

Index: services/ui/surfaces/compositor_frame_sink.h
diff --git a/services/ui/surfaces/display_compositor.h b/services/ui/surfaces/compositor_frame_sink.h
similarity index 70%
copy from services/ui/surfaces/display_compositor.h
copy to services/ui/surfaces/compositor_frame_sink.h
index 4ec50dedbc9b1a10e02f53216ccfcf6834dacf80..6ba22c5e87f34b698a370980e9e7c70efb998e4b 100644
--- a/services/ui/surfaces/display_compositor.h
+++ b/services/ui/surfaces/compositor_frame_sink.h
@@ -2,15 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef SERVICES_UI_SURFACES_DISPLAY_COMPOSITOR_H_
-#define SERVICES_UI_SURFACES_DISPLAY_COMPOSITOR_H_
+#ifndef SERVICES_UI_SURFACES_COMPOSITOR_FRAME_SINK_H_
+#define SERVICES_UI_SURFACES_COMPOSITOR_FRAME_SINK_H_
 
 #include "cc/surfaces/display_client.h"
 #include "cc/surfaces/surface.h"
 #include "cc/surfaces/surface_factory.h"
 #include "cc/surfaces/surface_factory_client.h"
 #include "cc/surfaces/surface_id_allocator.h"
-#include "services/ui/surfaces/surfaces_state.h"
+#include "services/ui/surfaces/display_compositor.h"
 #include "ui/gfx/native_widget_types.h"
 
 namespace cc {
@@ -22,22 +22,24 @@ class GpuChannelHost;
 }
 
 namespace ui {
+namespace surfaces {
 
 // TODO(fsamuel): This should become a mojo interface for the mus-gpu split.
 // TODO(fsamuel): This should not be a SurfaceFactoryClient.
-// The DisplayCompositor receives CompositorFrames from all sources,
+// The CompositorFrameSink receives CompositorFrames from all sources,
 // creates a top-level CompositorFrame once per tick, and generates graphical
 // output.
-class DisplayCompositor : public cc::SurfaceFactoryClient,
-                          public cc::DisplayClient {
+class CompositorFrameSink : public cc::SurfaceFactoryClient,
+                            public cc::DisplayClient {
  public:
-  DisplayCompositor(scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-                    gfx::AcceleratedWidget widget,
-                    scoped_refptr<gpu::GpuChannelHost> gpu_channel,
-                    const scoped_refptr<SurfacesState>& surfaces_state);
-  ~DisplayCompositor() override;
-
-  // DisplayCompositor embedders submit a CompositorFrame when content on the
+  CompositorFrameSink(
+      scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+      gfx::AcceleratedWidget widget,
+      scoped_refptr<gpu::GpuChannelHost> gpu_channel,
+      const scoped_refptr<DisplayCompositor>& display_compositor);
+  ~CompositorFrameSink() override;
+
+  // CompositorFrameSink embedders submit a CompositorFrame when content on the
   // display should be changed. A well-behaving embedder should only submit
   // a CompositorFrame once per BeginFrame tick. The callback is called the
   // first time this frame is used to draw, or if the frame is discarded.
@@ -45,7 +47,7 @@ class DisplayCompositor : public cc::SurfaceFactoryClient,
                              const base::Callback<void()>& callback);
 
   // TODO(fsamuel): This is used for surface hittesting and should not be
-  // exposed outside of DisplayCompositor.
+  // exposed outside of CompositorFrameSink.
   const cc::SurfaceId& surface_id() const { return surface_id_; }
 
   // This requests the display CompositorFrame be rendered and given to the
@@ -69,16 +71,17 @@ class DisplayCompositor : public cc::SurfaceFactoryClient,
   void DisplayDidDrawAndSwap() override;
 
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
-  scoped_refptr<SurfacesState> surfaces_state_;
+  scoped_refptr<DisplayCompositor> display_compositor_;
   cc::SurfaceFactory factory_;
   cc::SurfaceIdAllocator allocator_;
   cc::SurfaceId surface_id_;
 
   gfx::Size display_size_;
   std::unique_ptr<cc::Display> display_;
-  DISALLOW_COPY_AND_ASSIGN(DisplayCompositor);
+  DISALLOW_COPY_AND_ASSIGN(CompositorFrameSink);
 };
 
+}  // nanmespace surfaces
 }  // namespace ui
 
-#endif  // SERVICES_UI_SURFACES_DISPLAY_COMPOSITOR_H_
+#endif  // SERVICES_UI_SURFACES_COMPOSITOR_FRAME_SINK_H_