Blend TextureLayer background-color at draw time.

cc/quads/texture_draw_quad.h

Index: cc/quads/texture_draw_quad.h
diff --git a/cc/quads/texture_draw_quad.h b/cc/quads/texture_draw_quad.h
index 0b35568ac90307593a4eace5ebf1f9b0fbf528e1..00587e639e11ba4320c96d09292925f6739d2123 100644
--- a/cc/quads/texture_draw_quad.h
+++ b/cc/quads/texture_draw_quad.h
@@ -24,6 +24,7 @@ class CC_EXPORT TextureDrawQuad : public DrawQuad {
               gfx::PointF uv_top_left,
               gfx::PointF uv_bottom_right,
               const float vertex_opacity[4],
+              SkColor background_color,
               bool flipped);
 
   void SetAll(const SharedQuadState* shared_quad_state,
@@ -36,6 +37,7 @@ class CC_EXPORT TextureDrawQuad : public DrawQuad {
               gfx::PointF uv_top_left,
               gfx::PointF uv_bottom_right,
               const float vertex_opacity[4],
+              SkColor background_color,
               bool flipped);
 
   unsigned resource_id;
@@ -43,6 +45,7 @@ class CC_EXPORT TextureDrawQuad : public DrawQuad {
   gfx::PointF uv_top_left;
   gfx::PointF uv_bottom_right;
   float vertex_opacity[4];
+  SkColor background_color;
   bool flipped;
 
   virtual void IterateResources(const ResourceIteratorCallback& callback)