Blend TextureLayer background-color at draw time.

cc/quads/texture_draw_quad.cc

Index: cc/quads/texture_draw_quad.cc
diff --git a/cc/quads/texture_draw_quad.cc b/cc/quads/texture_draw_quad.cc
index 04c9511ab1e1a7efbb217484d7c6475f30e58510..5c9d8c4f172147286c0176eced4553d2eb5a25e6 100644
--- a/cc/quads/texture_draw_quad.cc
+++ b/cc/quads/texture_draw_quad.cc
@@ -12,6 +12,7 @@ namespace cc {
 TextureDrawQuad::TextureDrawQuad()
     : resource_id(0),
       premultiplied_alpha(false),
+      background_color(SK_ColorTRANSPARENT),
       flipped(false) {
   this->vertex_opacity[0] = 0.f;
   this->vertex_opacity[1] = 0.f;
@@ -28,7 +29,9 @@ void TextureDrawQuad::SetNew(const SharedQuadState* shared_quad_state,
                              unsigned resource_id, bool premultiplied_alpha,
                              gfx::PointF uv_top_left,
                              gfx::PointF uv_bottom_right,
-                             const float vertex_opacity[4], bool flipped) {
+                             const float vertex_opacity[4],
+                             SkColor background_color,
+                             bool flipped) {
   gfx::Rect visible_rect = rect;
   bool needs_blending = vertex_opacity[0] != 1.0f || vertex_opacity[1] != 1.0f
       || vertex_opacity[2] != 1.0f || vertex_opacity[3] != 1.0f;
@@ -42,6 +45,7 @@ void TextureDrawQuad::SetNew(const SharedQuadState* shared_quad_state,
   this->vertex_opacity[1] = vertex_opacity[1];
   this->vertex_opacity[2] = vertex_opacity[2];
   this->vertex_opacity[3] = vertex_opacity[3];
+  this->background_color = background_color;
   this->flipped = flipped;
 }
 
@@ -51,7 +55,9 @@ void TextureDrawQuad::SetAll(const SharedQuadState* shared_quad_state,
                              unsigned resource_id, bool premultiplied_alpha,
                              gfx::PointF uv_top_left,
                              gfx::PointF uv_bottom_right,
-                             const float vertex_opacity[4], bool flipped) {
+                             const float vertex_opacity[4],
+                             SkColor background_color,
+                             bool flipped) {
   DrawQuad::SetAll(shared_quad_state, DrawQuad::TEXTURE_CONTENT, rect,
                    opaque_rect, visible_rect, needs_blending);
   this->resource_id = resource_id;
@@ -62,6 +68,7 @@ void TextureDrawQuad::SetAll(const SharedQuadState* shared_quad_state,
   this->vertex_opacity[1] = vertex_opacity[1];
   this->vertex_opacity[2] = vertex_opacity[2];
   this->vertex_opacity[3] = vertex_opacity[3];
+  this->background_color = background_color;
   this->flipped = flipped;
 }