Mus: Introduce DisplayCompositorClient mojo interface

services/ui/ws/window_server.h

Index: services/ui/ws/window_server.h
diff --git a/services/ui/ws/window_server.h b/services/ui/ws/window_server.h
index 009811a8d9d8cda08da093f04fe539dadeba0f9a..3764a4504c6d3646f6bd3a70415c1349dc1a04b7 100644
--- a/services/ui/ws/window_server.h
+++ b/services/ui/ws/window_server.h
@@ -14,6 +14,7 @@
 
 #include "base/macros.h"
 #include "base/optional.h"
+#include "cc/ipc/display_compositor.mojom.h"
 #include "mojo/public/cpp/bindings/array.h"
 #include "mojo/public/cpp/bindings/binding.h"
 #include "services/ui/public/interfaces/window_manager_window_tree_factory.mojom.h"
@@ -51,7 +52,7 @@ class WindowServer : public ServerWindowDelegate,
                      public GpuServiceProxyDelegate,
                      public UserDisplayManagerDelegate,
                      public UserIdTrackerObserver,
-                     public DisplayCompositorClient {
+                     public cc::mojom::DisplayCompositorClient {
  public:
   explicit WindowServer(WindowServerDelegate* delegate);
   ~WindowServer() override;
@@ -339,7 +340,7 @@ class WindowServer : public ServerWindowDelegate,
   void OnGpuChannelEstablished(
       scoped_refptr<gpu::GpuChannelHost> gpu_channel) override;
 
-  // DisplayCompositorClient:
+  // cc::mojom::DisplayCompositorClient:
   void OnSurfaceCreated(const cc::SurfaceId& surface_id,
                         const gfx::Size& frame_size,
                         float device_scale_factor) override;
@@ -354,9 +355,6 @@ class WindowServer : public ServerWindowDelegate,
 
   WindowServerDelegate* delegate_;
 
-  // State for rendering into a Surface.
-  scoped_refptr<ui::DisplayCompositor> display_compositor_;
-
   // ID to use for next WindowTree.
   ClientSpecificId next_client_id_;
 
@@ -390,6 +388,11 @@ class WindowServer : public ServerWindowDelegate,
 
   WindowManagerWindowTreeFactorySet window_manager_window_tree_factory_set_;
 
+  mojo::Binding<cc::mojom::DisplayCompositorClient>
+      display_compositor_client_binding_;
+  // State for rendering into a Surface.
+  scoped_refptr<ui::DisplayCompositor> display_compositor_;
+
   DISALLOW_COPY_AND_ASSIGN(WindowServer);
 };