Mac: Clean up plumbing of accelerated widgets

gpu/ipc/service/image_transport_surface_mac.mm

Index: gpu/ipc/service/image_transport_surface_mac.mm
diff --git a/gpu/ipc/service/image_transport_surface_mac.mm b/gpu/ipc/service/image_transport_surface_mac.mm
index 8e12bff3d9137e6434425169407dac7d4b49fe02..cdd155bf2f7f9bc5f45c26df2bd7dee992b4c496 100644
--- a/gpu/ipc/service/image_transport_surface_mac.mm
+++ b/gpu/ipc/service/image_transport_surface_mac.mm
@@ -5,6 +5,7 @@
 #include "gpu/ipc/service/image_transport_surface.h"
 
 #include "base/macros.h"
+#include "gpu/ipc/service/image_transport_surface_overlay_mac.h"
 #include "gpu/ipc/service/pass_through_image_transport_surface.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gl/gl_surface_osmesa.h"
@@ -12,11 +13,6 @@
 
 namespace gpu {
 
-scoped_refptr<gl::GLSurface> ImageTransportSurfaceCreateNativeSurface(
-    GpuChannelManager* manager,
-    GpuCommandBufferStub* stub,
-    SurfaceHandle handle);
-
 namespace {
 
 // A subclass of GLSurfaceOSMesa that doesn't print an error message when
@@ -55,8 +51,7 @@
     case gl::kGLImplementationDesktopGL:
     case gl::kGLImplementationDesktopGLCoreProfile:
     case gl::kGLImplementationAppleGL:
-      return ImageTransportSurfaceCreateNativeSurface(manager, stub,
-                                                      surface_handle);
+      return new ImageTransportSurfaceOverlayMac(stub);
     case gl::kGLImplementationMockGL:
       return new gl::GLSurfaceStub;
     default: