cc:: Add remote mode to the compositor

cc/trees/compositor_mode.h

Index: cc/trees/compositor_mode.h
diff --git a/cc/trees/compositor_mode.h b/cc/trees/compositor_mode.h
index 649441966d1c1440fb4c1bd07a704f6aa2b452c1..5a0e9227d83706928b8d25f2926d551bb2116566 100644
--- a/cc/trees/compositor_mode.h
+++ b/cc/trees/compositor_mode.h
@@ -12,10 +12,16 @@ namespace cc {
 // 1) Safely cast Proxy to SingleThreadProxy to allow operations only supported
 // in SingleThreaded mode.
 // 2) Make decisions restricted to either browser(SingleThreaded) or renderer
-// compositors(Threaded).
-enum CompositorMode {
-  SingleThreaded,
-  Threaded,
+// compositors(Threaded/Remote).
+enum class CompositorMode {
+  // The main and impl components will be run on the same thread.
+  SINGLE_THREADED,
+
+  // The main and impl components be run on different threads.
+  THREADED,
+
+  // The main and impl components will be run across the network.
+  REMOTE,
 };
 
 }  // namespace cc