cc: Introduce CompositorMode enum.

cc/trees/compositor_mode.h

Index: cc/trees/compositor_mode.h
diff --git a/cc/base/resource_id.h b/cc/trees/compositor_mode.h
similarity index 55%
copy from cc/base/resource_id.h
copy to cc/trees/compositor_mode.h
index 84d00ad8e592b8c10310a8e31b26cf0f93e886b5..1453e451181e3ae4ac1d82bdba39e416f2921247 100644
--- a/cc/base/resource_id.h
+++ b/cc/trees/compositor_mode.h
@@ -2,15 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CC_BASE_RESOURCE_ID_H_
-#define CC_BASE_RESOURCE_ID_H_
-
-#include <stdint.h>
+#ifndef CC_TREES_COMPOSITOR_MODE_H_
+#define CC_TREES_COMPOSITOR_MODE_H_
 
 namespace cc {
 
-using ResourceId = uint32_t;
+enum CompositorMode {
+  SingleThreaded,
+  Threaded,

[vmpstr, 2015/12/07 18:50:09]

I'm kind of wondering if this should be MultiThreaded, but I guess this is
consistent with CreateThreaded/CreateSingleThreaded.

Can you leave a comment above the enum explaining where this is used and what
this affects?

[Khushal, 2015/12/07 21:49:26]

Yup. Wanted to keep it consistent with the LayerTreeHost Create methods.
Done.

+};
 
 }  // namespace cc
 
-#endif  // CC_BASE_RESOURCE_ID_H_
+#endif  // CC_TREES_COMPOSITOR_MODE_H_