Add hints for potential overlay promotion on android.

cc/output/overlay_processor.h

Index: cc/output/overlay_processor.h
diff --git a/cc/output/overlay_processor.h b/cc/output/overlay_processor.h
index 01c28d253174aca976d65bff43138477b5146c4b..945d76e4517aacf280d125bb54bbeaf2f111143b 100644
--- a/cc/output/overlay_processor.h
+++ b/cc/output/overlay_processor.h
@@ -9,6 +9,7 @@
 
 #include "base/macros.h"
 #include "cc/base/cc_export.h"
+#include "cc/base/resource_id.h"
 #include "cc/output/ca_layer_overlay.h"
 #include "cc/output/overlay_candidate.h"
 #include "cc/quads/render_pass.h"
@@ -47,6 +48,8 @@ class CC_EXPORT OverlayProcessor {
                           CALayerOverlayList* ca_layer_overlays,
                           gfx::Rect* damage_rect);
 
+  bool IsResourcePromotable(ResourceId resource_id);
+
  protected:
   StrategyList strategies_;
   OutputSurface* surface_;