Define step timing function for the cc animation framework.

Source/core/animation/CompositorAnimationsTestHelper.h

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 90 matching lines @@
     MOCK_METHOD0(delete_, void());
     ~WebCompositorAnimationMock() { delete_(); }
 };
 
 template<typename CurveType, WebCompositorAnimationCurve::AnimationCurveType CurveId, typename KeyframeType>
 class WebCompositorAnimationCurveMock : public CurveType {
 public:
     MOCK_METHOD1_T(add, void(const KeyframeType&));
     MOCK_METHOD2_T(add, void(const KeyframeType&, WebCompositorAnimationCurve::TimingFunctionType));
     MOCK_METHOD5_T(add, void(const KeyframeType&, double, double, double, double));
+    MOCK_METHOD3_T(add, void(const KeyframeType&, int steps, float stepsStartOffset));
 
     MOCK_CONST_METHOD1_T(getValue, float(double)); // Only on WebFloatAnimationCurve, but can't hurt to have here.
 
     virtual WebCompositorAnimationCurve::AnimationCurveType type() const { return CurveId; };
 
     MOCK_METHOD0(delete_, void());
     ~WebCompositorAnimationCurveMock() { delete_(); }
 };
 
 using WebFloatAnimationCurveMock = WebCompositorAnimationCurveMock<WebFloatAnimationCurve, WebCompositorAnimationCurve::AnimationCurveTypeFloat, WebFloatKeyframe>;
@@ skipping 44 matching lines @@
     void setCompositorForTesting(WebCompositorSupportMock& mock)
     {
         ASSERT(!m_mockCompositor);
         m_mockCompositor = &mock;
     }
 };
 
 }
 
 #endif