Use base::FooValue::From() to simplify gpu code.

gpu/tools/compositor_model_bench/forward_render_model.cc

 // Copyright (c) 2011 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 "gpu/tools/compositor_model_bench/forward_render_model.h"
 
 #include <stddef.h>
 
 #include <cstdlib>
 #include <vector>
@@ skipping 21 matching lines @@
     ConfigAndActivateShaderForTiling(l);
     // Now that we capture root layer tiles, a layer without tiles
     // should not get drawn.
     for (size_t n = 0; n < l->num_tiles(); ++n) {
       const Tile* i = l->tile(n);
       DrawTileQuad(i->texID, i->x, i->y);
     }
   }
 };
 
-ForwardRenderSimulator::ForwardRenderSimulator(RenderNode* root,
+ForwardRenderSimulator::ForwardRenderSimulator(std::unique_ptr<RenderNode> root,
                                                int window_width,
                                                int window_height)
-    : RenderModelSimulator(root) {
-  textures_.reset(new TextureGenerator(root));
+    : RenderModelSimulator(std::move(root)) {
+  textures_.reset(new TextureGenerator(root_.get()));
   visitor_.reset(new ForwardRenderNodeVisitor());
   glViewport(0, 0, window_width, window_height);
   glDisable(GL_DEPTH_TEST);
   glDisable(GL_CULL_FACE);
   glEnable(GL_BLEND);
   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 }
 
 ForwardRenderSimulator::~ForwardRenderSimulator() {
 }
 
 void ForwardRenderSimulator::Update() {
   glClearColor(0, 0, 1, 1);
   glColorMask(true, true, true, true);
   glClear(GL_COLOR_BUFFER_BIT);
   glColorMask(true, true, true, false);
   BeginFrame();
   root_->Accept(visitor_.get());
 }
 
 void ForwardRenderSimulator::Resize(int width, int height) {
   glViewport(0, 0, width, height);
 }