Implement pinch-zoom scaling for main-frame scrollbars and pinch-zoom overlay scrollbars.

cc/scrollbar_layer.h

Index: cc/scrollbar_layer.h
diff --git a/cc/scrollbar_layer.h b/cc/scrollbar_layer.h
index e26cbdea2875cc2071a980d34512181f937d8d19..a7a42c19489e01eb8e2a96069bf69d1f1a98a2b1 100644
--- a/cc/scrollbar_layer.h
+++ b/cc/scrollbar_layer.h
@@ -27,13 +27,26 @@ public:
         scoped_ptr<WebKit::WebScrollbar>,
         scoped_ptr<ScrollbarThemePainter>,
         scoped_ptr<WebKit::WebScrollbarThemeGeometry>,
+        int scrollLayerId, bool isPinchZoomScrollbar = false);
+
+    // This version of create() only called when creating pinch zoom scrollbars.
+    static scoped_refptr<ScrollbarLayer> create(
+        scoped_ptr<WebKit::WebScrollbar>,
+        scoped_ptr<ScrollbarThemePainter>,
         int scrollLayerId);
 
+    static void setDefaultGeometry(WebKit::WebScrollbarThemeGeometry*);
+    static WebKit::WebScrollbarThemeGeometry* cloneDefaultGeometry();
+    static void setDefaultUsesOverlayScrollbars(bool);
+    static bool defaultUsesOverlayScrollbars() { return s_usesOverlayScrollbars; }
+
     int scrollLayerId() const { return m_scrollLayerId; }
     void setScrollLayerId(int id);
 
     WebKit::WebScrollbar::Orientation orientation() const;
 
+    bool isPinchZoomScrollbar() { return m_isPinchZoomScrollbar; }
+
     // Layer interface
     virtual void setTexturePriorities(const PriorityCalculator&) OVERRIDE;
     virtual void update(ResourceUpdateQueue&, const OcclusionTracker*, RenderingStats*) OVERRIDE;
@@ -53,7 +66,7 @@ protected:
         scoped_ptr<WebKit::WebScrollbar>,
         scoped_ptr<ScrollbarThemePainter>,
         scoped_ptr<WebKit::WebScrollbarThemeGeometry>,
-        int scrollLayerId);
+        int scrollLayerId, bool isPinchZoomScrollbar);
     virtual ~ScrollbarLayer();
 
 private:
@@ -66,6 +79,9 @@ private:
     int maxTextureSize();
     float clampScaleToMaxTextureSize(float scale);
 
+    static scoped_ptr<WebKit::WebScrollbarThemeGeometry> s_defaultGeometry;
+    static bool s_usesOverlayScrollbars;

[aelias_OOO_until_Jul13, 2013/02/06 19:02:45]

Please avoid statics.

+
     scoped_ptr<WebKit::WebScrollbar> m_scrollbar;
     scoped_ptr<ScrollbarThemePainter> m_painter;
     scoped_ptr<WebKit::WebScrollbarThemeGeometry> m_geometry;
@@ -73,6 +89,7 @@ private:
     int m_scrollLayerId;
 
     unsigned m_textureFormat;
+    bool m_isPinchZoomScrollbar;
 
     gfx::RectF m_dirtyRect;