Mac Overlays: Allow SolidColor and Tile quads to be candidates for overlays.

cc/output/overlay_candidate_validator.h

Index: cc/output/overlay_candidate_validator.h
diff --git a/cc/output/overlay_candidate_validator.h b/cc/output/overlay_candidate_validator.h
index 8586b4de1703d9f31b3bd4841fcc7ed73a2b8866..4293069b40cb5f247cb7bca861e041b61f2af336 100644
--- a/cc/output/overlay_candidate_validator.h
+++ b/cc/output/overlay_candidate_validator.h
@@ -13,6 +13,8 @@
 
 namespace cc {
 
+class DrawQuad;
+
 // This class that can be used to answer questions about possible overlay
 // configurations for a particular output device.
 class CC_EXPORT OverlayCandidateValidator {
@@ -20,6 +22,8 @@ class CC_EXPORT OverlayCandidateValidator {
   // Populates a list of strategies that may work with this validator.
   virtual void GetStrategies(OverlayProcessor::StrategyList* strategies) = 0;
 
+  virtual bool IsSupportedQuad(const DrawQuad* quad) = 0;
+
   // A list of possible overlay candidates is presented to this function.
   // The expected result is that those candidates that can be in a separate
   // plane are marked with |overlay_handled| set to true, otherwise they are