Convert offscreen canvas to use FrameSinkManagerHost.

content/browser/compositor/surface_utils.h

Index: content/browser/compositor/surface_utils.h
diff --git a/content/browser/compositor/surface_utils.h b/content/browser/compositor/surface_utils.h
index 804e387b2523785dfc28f3c4d58fe0415becd652..8b7c928e462043e0a24ac263f88da44e4e5cf62f 100644
--- a/content/browser/compositor/surface_utils.h
+++ b/content/browser/compositor/surface_utils.h
@@ -16,6 +16,9 @@
 namespace cc {
 class CopyOutputResult;
 class SurfaceManager;
+namespace mojom {
+class DisplayCompositor;
+}  // namespace mojom
 }  // namespace cc
 
 namespace content {
@@ -24,6 +27,8 @@ CONTENT_EXPORT cc::FrameSinkId AllocateFrameSinkId();
 
 CONTENT_EXPORT cc::SurfaceManager* GetSurfaceManager();
 
+CONTENT_EXPORT cc::mojom::DisplayCompositor* GetDisplayCompositor();
+
 void CopyFromCompositingSurfaceHasResult(
     const gfx::Size& dst_size_in_pixel,
     const SkColorType color_type,