cc: Support animating scroll offset

cc/test/animation_test_common.h

Index: cc/test/animation_test_common.h
diff --git a/cc/test/animation_test_common.h b/cc/test/animation_test_common.h
index 008af87d0db3142745a7695e9680e6e2860f61eb..1205bf30929cc90c93e0d4be2bb0f7de66f70fdc 100644
--- a/cc/test/animation_test_common.h
+++ b/cc/test/animation_test_common.h
@@ -9,7 +9,9 @@
 #include "cc/animation/animation_curve.h"
 #include "cc/animation/layer_animation_controller.h"
 #include "cc/animation/layer_animation_value_observer.h"
+#include "cc/animation/layer_animation_value_provider.h"
 #include "cc/output/filter_operations.h"
+#include "cc/test/geometry_test_utils.h"
 
 namespace cc {
 class LayerImpl;
@@ -73,12 +75,14 @@ class FakeLayerAnimationValueObserver : public LayerAnimationValueObserver {
   virtual void OnFilterAnimated(const FilterOperations& filters) OVERRIDE;
   virtual void OnOpacityAnimated(float opacity) OVERRIDE;
   virtual void OnTransformAnimated(const gfx::Transform& transform) OVERRIDE;
+  virtual void OnScrollOffsetAnimated(gfx::Vector2dF scroll_offset) OVERRIDE;
   virtual void OnAnimationWaitingForDeletion() OVERRIDE;
   virtual bool IsActive() const OVERRIDE;
 
   const FilterOperations& filters() const { return filters_; }
   float opacity() const  { return opacity_; }
   const gfx::Transform& transform() const { return transform_; }
+  gfx::Vector2dF scroll_offset() { return scroll_offset_; }
 
   bool animation_waiting_for_deletion() {
     return animation_waiting_for_deletion_;
@@ -88,6 +92,7 @@ class FakeLayerAnimationValueObserver : public LayerAnimationValueObserver {
   FilterOperations filters_;
   float opacity_;
   gfx::Transform transform_;
+  gfx::Vector2dF scroll_offset_;
   bool animation_waiting_for_deletion_;
 };
 
@@ -97,6 +102,18 @@ class FakeInactiveLayerAnimationValueObserver
   virtual bool IsActive() const OVERRIDE;
 };
 
+class FakeLayerAnimationValueProvider : public LayerAnimationValueProvider {
+ public:
+  virtual gfx::Vector2dF ScrollOffsetForAnimation() const OVERRIDE;
+
+  void set_scroll_offset(gfx::Vector2dF scroll_offset) {
+    scroll_offset_ = scroll_offset;
+  }
+
+ private:
+  gfx::Vector2dF scroll_offset_;
+};
+
 int AddOpacityTransitionToController(LayerAnimationController* controller,
                                      double duration,
                                      float start_opacity,