Remove CompositeAndReadback from LayerTreeHost(Impl) and the Proxys.

cc/output/direct_renderer.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/output/direct_renderer.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/containers/hash_tables.h"
@@ skipping 121 matching lines @@
     : Renderer(client, settings),
       output_surface_(output_surface),
       resource_provider_(resource_provider),
       overlay_processor_(
           new OverlayProcessor(output_surface, resource_provider)) {
   overlay_processor_->Initialize();
 }
 
 DirectRenderer::~DirectRenderer() {}
 
-bool DirectRenderer::CanReadPixels() const { return true; }
-
 void DirectRenderer::SetEnlargePassTextureAmountForTesting(
     const gfx::Vector2d& amount) {
   enlarge_pass_texture_amount_ = amount;
 }
 
 void DirectRenderer::DecideRenderPassAllocationsForFrame(
     const RenderPassList& render_passes_in_draw_order) {
   if (!resource_provider_)
     return;
 
@@ skipping 295 matching lines @@
   ScopedResource* texture = render_pass_textures_.get(id);
   return texture && texture->id();
 }
 
 // static
 gfx::Size DirectRenderer::RenderPassTextureSize(const RenderPass* render_pass) {
   return render_pass->output_rect.size();
 }
 
 }  // namespace cc