cc: Add OutputSurface state snapshots.

cc/output/direct_renderer.cc

Index: cc/output/direct_renderer.cc
diff --git a/cc/output/direct_renderer.cc b/cc/output/direct_renderer.cc
index cc7fd12c67002cf9dd367ff183eebf9d9792a2d6..54214ef07231770af5984bdbd35e38c00fe0fa0a 100644
--- a/cc/output/direct_renderer.cc
+++ b/cc/output/direct_renderer.cc
@@ -307,6 +307,12 @@ void DirectRenderer::DrawFrame(RenderPassList* render_passes_in_draw_order,
   render_passes_in_draw_order->clear();
 }
 
+void DirectRenderer::ReadbackSwappedOverlayTextures(
+    std::vector<SkBitmap>* bitmaps,
+    const base::Callback<void(bool)>& callback) {
+  callback.Run(false);
+}
+
 gfx::Rect DirectRenderer::ComputeScissorRectForRenderPass(
     const DrawingFrame* frame) {
   if (frame->current_render_pass == frame->root_render_pass)