Pinch/Zoom Infrastructure & Plumbing CL

cc/layers/scrollbar_layer_impl_base.h

Index: cc/layers/scrollbar_layer_impl_base.h
diff --git a/cc/layers/scrollbar_layer_impl_base.h b/cc/layers/scrollbar_layer_impl_base.h
index 55ade6ab04f18b5ab7691ca3e4555903046ca902..cba60d286221d310efaf6b11870a83e924553580 100644
--- a/cc/layers/scrollbar_layer_impl_base.h
+++ b/cc/layers/scrollbar_layer_impl_base.h
@@ -7,6 +7,7 @@
 
 #include "cc/base/cc_export.h"
 #include "cc/input/scrollbar.h"
+#include "cc/layers/layer.h"
 #include "cc/layers/layer_impl.h"
 
 namespace cc {
@@ -15,8 +16,16 @@ class LayerTreeImpl;
 
 class CC_EXPORT ScrollbarLayerImplBase : public LayerImpl {
  public:
-  int ScrollLayerId() const { return scroll_layer_id_; }
-  void set_scroll_layer_id(int id) { scroll_layer_id_ = id; }
+  int ScrollLayerId() const {
+    return scroll_layer_ ? scroll_layer_->id() : Layer::INVALID_ID;
+  }
+  void ClearScrollLayer() { scroll_layer_ = NULL; }
+  void SetScrollLayerById(int id);
+  int ClipLayerId() const {
+    return clip_layer_ ? clip_layer_->id() : Layer::INVALID_ID;
+  }
+  void ClearClipLayer() { clip_layer_ = NULL; }
+  void SetClipLayerById(int id);
 
   float current_pos() const { return current_pos_; }
   void SetCurrentPos(float current_pos);
@@ -48,12 +57,15 @@ class CC_EXPORT ScrollbarLayerImplBase : public LayerImpl {
     thumb_thickness_scale_factor_ = thumb_thickness_scale_factor;
   }
 
+  void ScrollbarParametersDidChange();
+  bool opacity_can_animate() { return opacity_can_animate_; }
+
  protected:
   ScrollbarLayerImplBase(LayerTreeImpl* tree_impl,
                          int id,
                          ScrollbarOrientation orientation,
                          bool is_left_side_vertical_scrollbar);
-  virtual ~ScrollbarLayerImplBase() {}
+  virtual ~ScrollbarLayerImplBase();
 
   gfx::Rect ScrollbarLayerRectToContentRect(gfx::RectF layer_rect) const;
 
@@ -68,7 +80,8 @@ class CC_EXPORT ScrollbarLayerImplBase : public LayerImpl {
   virtual int TrackStart() const = 0;
 
  private:
-  int scroll_layer_id_;
+  LayerImpl* scroll_layer_;
+  LayerImpl* clip_layer_;
   bool is_overlay_scrollbar_;
 
   float thumb_thickness_scale_factor_;
@@ -83,7 +96,11 @@ class CC_EXPORT ScrollbarLayerImplBase : public LayerImpl {
 
   float visible_to_total_length_ratio_;
 
+
   DISALLOW_COPY_AND_ASSIGN(ScrollbarLayerImplBase);
+
+ protected:
+  bool opacity_can_animate_;
 };
 
 }  // namespace cc