Add support for inverse transform animations.

ui/compositor/transform_animation_curve_adapter.h

 // Copyright (c) 2012 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 UI_COMPOSITOR_TRANSFORM_ANIMATION_CURVE_ADAPTER_H_
 #define UI_COMPOSITOR_TRANSFORM_ANIMATION_CURVE_ADAPTER_H_
 
 #include "base/time/time.h"
 #include "cc/animation/animation_curve.h"
 #include "ui/base/animation/tween.h"
@@ skipping 18 matching lines @@
 
  private:
   Tween::Type tween_type_;
   gfx::Transform initial_value_;
   gfx::Transform target_value_;
   gfx::DecomposedTransform decomposed_initial_value_;
   gfx::DecomposedTransform decomposed_target_value_;
   base::TimeDelta duration_;
 };
 
+class CounterTransformCurveAdapter :public cc::TransformAnimationCurve {
+ public:
+  CounterTransformCurveAdapter(TransformAnimationCurveAdapter parent_curve,
+                               gfx::Transform initial_value,
+                               base::TimeDelta duration);
+
+  virtual ~CounterTransformCurveAdapter();
+
+  virtual double Duration() const OVERRIDE;
+  virtual scoped_ptr<AnimationCurve> Clone() const OVERRIDE;
+  virtual gfx::Transform GetValue(double t) const OVERRIDE;
+
+ private:
+  TransformAnimationCurveAdapter parent_curve_;
+  gfx::Transform initial_value_;
+  gfx::Transform effective_initial_value_;
+  base::TimeDelta duration_;
+};
+
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_TRANSFORM_ANIMATION_CURVE_ADAPTER_H_