cc: Adding support for RGBA_4444 tile textures

cc/output/gl_renderer.cc

Index: cc/output/gl_renderer.cc
diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index a80feac4ecc9f97f3fd5e731d99a43cc7ea98a99..c8686e58c186af7d6846fea7992d97387435a970 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -1704,9 +1704,20 @@ void GLRenderer::DrawPictureQuad(const DrawingFrame* frame,
   quad->picture_pile->RasterToBitmap(&canvas, quad->content_rect,
                                      quad->contents_scale, NULL);
 
+  const uint8_t* bitmap_pixels = NULL;
+  if (resource_provider_->best_texture_type() == ResourceProvider::RGBA_4444) {
+    on_demand_tile_raster_bitmap_.copyTo(
+        &on_demand_tile_raster_bitmap_4444_, SkBitmap::kARGB_4444_Config);
+    bitmap_pixels = reinterpret_cast<uint8_t*>(
+        on_demand_tile_raster_bitmap_4444_.getPixels());
+  } else {
+    bitmap_pixels = reinterpret_cast<uint8_t*>(
+        on_demand_tile_raster_bitmap_.getPixels());
+  }
+
   resource_provider_->SetPixels(
       on_demand_tile_raster_resource_id_,
-      reinterpret_cast<uint8_t*>(on_demand_tile_raster_bitmap_.getPixels()),
+      bitmap_pixels,
       gfx::Rect(quad->texture_size),
       gfx::Rect(quad->texture_size),
       gfx::Vector2d());