Make scroll offset type of float in cc

cc/layers/layer_impl.h

Index: cc/layers/layer_impl.h
diff --git a/cc/layers/layer_impl.h b/cc/layers/layer_impl.h
index 65143ab514c386de3cc217c8f73cbd467dfab298..d666c8b513074a07a872d04536fa18bb18c1c840 100644
--- a/cc/layers/layer_impl.h
+++ b/cc/layers/layer_impl.h
@@ -376,10 +376,10 @@ class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
   void SetScrollOffsetDelegate(ScrollOffsetDelegate* scroll_offset_delegate);
   bool IsExternalFlingActive() const;
 
-  void SetScrollOffset(const gfx::Vector2d& scroll_offset);
-  void SetScrollOffsetAndDelta(const gfx::Vector2d& scroll_offset,
+  void SetScrollOffset(const gfx::Vector2dF& scroll_offset);
+  void SetScrollOffsetAndDelta(const gfx::Vector2dF& scroll_offset,
                                const gfx::Vector2dF& scroll_delta);
-  gfx::Vector2d scroll_offset() const { return scroll_offset_; }
+  gfx::Vector2dF scroll_offset() const { return scroll_offset_; }
 
   gfx::Vector2d MaxScrollOffset() const;
   gfx::Vector2dF ClampScrollToMaxScrollOffset();
@@ -390,8 +390,8 @@ class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
 
   gfx::Vector2dF TotalScrollOffset() const;
 
-  void SetSentScrollDelta(const gfx::Vector2d& sent_scroll_delta);
-  gfx::Vector2d sent_scroll_delta() const { return sent_scroll_delta_; }
+  void SetSentScrollDelta(const gfx::Vector2dF& sent_scroll_delta);
+  gfx::Vector2dF sent_scroll_delta() const { return sent_scroll_delta_; }
 
   // Returns the delta of the scroll that was outside of the bounds of the
   // initial scroll
@@ -606,7 +606,7 @@ class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
   gfx::Point3F transform_origin_;
   gfx::Size bounds_;
   gfx::Vector2dF bounds_delta_;
-  gfx::Vector2d scroll_offset_;
+  gfx::Vector2dF scroll_offset_;
   ScrollOffsetDelegate* scroll_offset_delegate_;
   LayerImpl* scroll_clip_layer_;
   bool scrollable_ : 1;
@@ -649,7 +649,7 @@ class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
   LayerPositionConstraint position_constraint_;
 
   gfx::Vector2dF scroll_delta_;
-  gfx::Vector2d sent_scroll_delta_;
+  gfx::Vector2dF sent_scroll_delta_;
   gfx::Vector2dF last_scroll_offset_;
 
   int num_descendants_that_draw_content_;