Add API for hit testing layer_impl touchEventHandlerRegions from the host

cc/input_handler.h

Index: cc/input_handler.h
diff --git a/cc/input_handler.h b/cc/input_handler.h
index 6898c1fb0625ade007185bb568ceeb346e777bce..2538fb0850f2658e91d93516d3645a2df7592a95 100644
--- a/cc/input_handler.h
+++ b/cc/input_handler.h
@@ -11,6 +11,7 @@
 
 namespace gfx {
 class Point;
+class PointF;
 class Vector2d;
 }
 
@@ -62,6 +63,8 @@ public:
     // Request another callback to InputHandler::animate().
     virtual void scheduleAnimation() = 0;
 
+    virtual bool checkTouchEventHandlerRegionHit(const gfx::Point&) = 0;
+
 protected:
     InputHandlerClient() { }
     virtual ~InputHandlerClient() { }