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

cc/layers/render_surface_impl.cc

Index: cc/layers/render_surface_impl.cc
diff --git a/cc/layers/render_surface_impl.cc b/cc/layers/render_surface_impl.cc
index 6c0ec3435d01fff4274794e76093aed3eb1c285c..b37376f1df41a3155e8423e52c6d3c15167cb582 100644
--- a/cc/layers/render_surface_impl.cc
+++ b/cc/layers/render_surface_impl.cc
@@ -215,6 +215,10 @@ void RenderSurfaceImpl::AppendQuads(QuadSink* quad_sink,
       ContentsChanged() ? content_rect_ : gfx::Rect();
 
   scoped_ptr<RenderPassDrawQuad> quad = RenderPassDrawQuad::Create();
+  gfx::Transform scale =
+      owning_layer_->draw_properties().target_space_transform;

[danakj, 2014/03/07 17:35:44]

Invert the order here.

Transform Scale() should happen first, then PreConcat the
target_space_transform.

[Stephen White, 2014/03/07 20:45:58]

Done (probably shouldn't make a difference if it really is just a scale, but
ok).

+  scale.Scale(owning_layer_->contents_scale_x(),
+              owning_layer_->contents_scale_y());
   quad->SetNew(shared_quad_state,
                content_rect_,
                render_pass_id,
@@ -223,7 +227,8 @@ void RenderSurfaceImpl::AppendQuads(QuadSink* quad_sink,
                contents_changed_since_last_frame,
                mask_uv_rect,
                owning_layer_->filters(),
-               owning_layer_->background_filters());
+               owning_layer_->background_filters(),
+               scale);
   quad_sink->Append(quad.PassAs<DrawQuad>(), append_quads_data);
 }