Implement hidpi and pinch-zoom scaling of filter params in cc.

cc/quads/render_pass_draw_quad.h

Index: cc/quads/render_pass_draw_quad.h
diff --git a/cc/quads/render_pass_draw_quad.h b/cc/quads/render_pass_draw_quad.h
index 1f6217ddc8c65bc1a505573b849cd568a92800d3..b0a51aa2a460d6bfb464ed13dd961194dbbdc2b4 100644
--- a/cc/quads/render_pass_draw_quad.h
+++ b/cc/quads/render_pass_draw_quad.h
@@ -29,7 +29,8 @@ class CC_EXPORT RenderPassDrawQuad : public DrawQuad {
               const gfx::Rect& contents_changed_since_last_frame,
               const gfx::RectF& mask_uv_rect,
               const FilterOperations& filters,
-              const FilterOperations& background_filters);
+              const FilterOperations& background_filters,
+              const gfx::Vector2dF& scale);
 
   void SetAll(const SharedQuadState* shared_quad_state,
               const gfx::Rect& rect,
@@ -42,7 +43,8 @@ class CC_EXPORT RenderPassDrawQuad : public DrawQuad {
               const gfx::Rect& contents_changed_since_last_frame,
               const gfx::RectF& mask_uv_rect,
               const FilterOperations& filters,
-              const FilterOperations& background_filters);
+              const FilterOperations& background_filters,
+              const gfx::Vector2dF& scale);
 
   scoped_ptr<RenderPassDrawQuad> Copy(
       const SharedQuadState* copied_shared_quad_state,
@@ -60,6 +62,7 @@ class CC_EXPORT RenderPassDrawQuad : public DrawQuad {
   // Post-processing filters, applied to the pixels showing through the
   // background of the render pass, from behind it.
   FilterOperations background_filters;
+  gfx::Vector2dF scale;

[danakj, 2014/03/07 20:54:05]

How about calling it |filters_scale|, move it up beside |filters| and describe
what it's for in a comment.

Use the same name for the arguments above then.

[Stephen White, 2014/03/07 21:54:14]

Done.

 
   virtual void IterateResources(const ResourceIteratorCallback& callback)
       OVERRIDE;