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..3db10c64a9dc39be2465fcbb3511ac6261a84f51 100644
--- a/cc/quads/texture_draw_quad.h
+++ b/cc/quads/texture_draw_quad.h
@@ -23,6 +23,7 @@ class CC_EXPORT TextureDrawQuad : public DrawQuad {
               bool premultiplied_alpha,
               gfx::PointF uv_top_left,
               gfx::PointF uv_bottom_right,
+              SkColor background_color,
               const float vertex_opacity[4],
               bool flipped);
 
@@ -35,6 +36,7 @@ class CC_EXPORT TextureDrawQuad : public DrawQuad {
               bool premultiplied_alpha,
               gfx::PointF uv_top_left,
               gfx::PointF uv_bottom_right,
+              SkColor background_color,
               const float vertex_opacity[4],
               bool flipped);
 
@@ -42,6 +44,7 @@ class CC_EXPORT TextureDrawQuad : public DrawQuad {
   bool premultiplied_alpha;
   gfx::PointF uv_top_left;
   gfx::PointF uv_bottom_right;
+  SkColor background_color;
   float vertex_opacity[4];
   bool flipped;