Rework View Layer Draw() to use the Layer::DrawTree() method and the LayerDelegate.

aura/window.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 "aura/window.h"
 
 #include <algorithm>
 
 #include "aura/desktop.h"
 #include "aura/event.h"
@@ skipping 36 matching lines @@
 void Window::Init() {
   layer_.reset(new ui::Layer(Desktop::GetInstance()->compositor()));
   layer_->set_delegate(this);
 }
 
 void Window::SetVisibility(Visibility visibility) {
   if (visibility_ == visibility)
     return;
 
   visibility_ = visibility;
-  if (visibility_ != VISIBILITY_HIDDEN)
+  layer_->set_visible(visibility_ != VISIBILITY_HIDDEN);
+  if (layer_->visible())
     SchedulePaint();
 }
 
 void Window::SetBounds(const gfx::Rect& bounds, int anim_ms) {
   // TODO: support anim_ms
   // TODO: funnel this through the Desktop.
   bool was_move = bounds_.size() == bounds.size();
   bounds_ = bounds;
   layer_->SetBounds(bounds);
   if (was_move)
@@ skipping 30 matching lines @@
   const Windows::iterator i(std::find(children_.begin(), children_.end(),
                                       child));
   DCHECK(i != children_.end());
   children_.erase(i);
 
   // TODO(beng): this obviously has to handle different window types.
   children_.insert(children_.begin() + children_.size(), child);
   SchedulePaintInRect(gfx::Rect());
 }
 
-void Window::DrawTree() {
-  Draw();
-  for (Windows::iterator i = children_.begin(); i != children_.end(); ++i)
-    (*i)->DrawTree();
-}
-
 void Window::AddChild(Window* child) {
   DCHECK(std::find(children_.begin(), children_.end(), child) ==
       children_.end());
   child->parent_ = this;
   layer_->Add(child->layer_.get());
   children_.push_back(child);
 }
 
 void Window::RemoveChild(Window* child) {
   Windows::iterator i = std::find(children_.begin(), children_.end(), child);
@@ skipping 37 matching lines @@
     if (child->HitTest(point_in_child_coords))
       return child->GetEventHandlerForPoint(point_in_child_coords);
   }
   return this;
 }
 
 internal::FocusManager* Window::GetFocusManager() {
   return parent_ ? parent_->GetFocusManager() : NULL;
 }
 
-void Window::Draw() {
-  if (visibility_ != VISIBILITY_HIDDEN)
-    layer_->Draw();
-}
-
 void Window::SchedulePaint() {
   SchedulePaintInRect(gfx::Rect(0, 0, bounds_.width(), bounds_.height()));
 }
 
-void Window::OnPaint(gfx::Canvas* canvas) {
-  delegate_->OnPaint(canvas);
+void Window::OnPaintLayer(gfx::Canvas* canvas) {
+  if (delegate_)
+    delegate_->OnPaint(canvas);
 }
 
 }  // namespace aura