Adds an interface to SurfaceHittestDelegate in order to override

cc/surfaces/surface_hittest_delegate.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_SURFACES_SURFACE_HITTEST_DELEGATE_H_
 #define CC_SURFACES_SURFACE_HITTEST_DELEGATE_H_
 
 namespace gfx {
 class Point;
 }  // namespace gfx
 
 namespace cc {
 
 class SurfaceDrawQuad;
 
 // Clients of SurfaceHittest can provide a SurfaceHittestDelegate implementation
 // to override the hit target based on metadata outside of the Surfaces system.
 class SurfaceHittestDelegate {
  public:
   // Return true if this delegate rejects this |surface_quad| as a candidate hit
   // target.
   virtual bool RejectHitTarget(const SurfaceDrawQuad* surface_quad,
                                const gfx::Point& point_in_quad_space) = 0;
+
+  // Return true if this delegate accepts this |surface_quad| as a candidate hit
+  // target.
+  virtual bool AcceptHitTarget(const SurfaceDrawQuad* surface_quad,
+                               const gfx::Point& point_in_quad_space) = 0;
 };
 
 }  // namespace cc
 
 #endif  // CC_SURFACES_SURFACE_HITTEST_DELEGATE_H_