desktop-views: Create one fewer aura::Window for each widget.

ui/views/widget/desktop_aura/desktop_native_widget_aura.cc

Index: ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
diff --git a/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc b/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
index 544da363f138105136afeeac5bfe589614cc8649..24cca0c9a39dbf2657a28b6fb14a22ad8d225561 100644
--- a/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
+++ b/ui/views/widget/desktop_aura/desktop_native_widget_aura.cc
@@ -239,7 +239,6 @@ DesktopNativeWidgetAura::DesktopNativeWidgetAura(
     internal::NativeWidgetDelegate* delegate)
     : desktop_window_tree_host_(NULL),
       ownership_(Widget::InitParams::NATIVE_WIDGET_OWNS_WIDGET),
-      content_window_container_(NULL),
       content_window_(new aura::Window(this)),
       native_widget_delegate_(delegate),
       last_drop_operation_(ui::DragDropTypes::DRAG_NONE),
@@ -417,11 +416,6 @@ void DesktopNativeWidgetAura::InitNativeWidget(
   content_window_->Init(params.layer_type);
   wm::SetShadowElevation(content_window_, wm::ShadowElevation::NONE);
 
-  content_window_container_ = new aura::Window(NULL);
-  content_window_container_->Init(ui::LAYER_NOT_DRAWN);
-  content_window_container_->Show();
-  content_window_container_->AddChild(content_window_);
-
   if (!desktop_window_tree_host_) {
     desktop_window_tree_host_ =
         params.desktop_window_tree_host
@@ -431,7 +425,7 @@ void DesktopNativeWidgetAura::InitNativeWidget(
   }
   desktop_window_tree_host_->Init(content_window_, params);
 
-  host_->window()->AddChild(content_window_container_);
+  host_->window()->AddChild(content_window_);
   host_->window()->SetProperty(kDesktopNativeWidgetAuraKey, this);
 
   host_->window()->AddObserver(new RootWindowDestructionObserver(this));
@@ -518,8 +512,6 @@ void DesktopNativeWidgetAura::InitNativeWidget(
     aura::client::SetVisibilityClient(host_->window(),
                                       visibility_controller_.get());
     wm::SetChildWindowVisibilityChangesAnimated(host_->window());
-    wm::SetChildWindowVisibilityChangesAnimated(
-        content_window_container_);
   }
 
   if (params.type == Widget::InitParams::TYPE_WINDOW) {
@@ -1167,9 +1159,6 @@ void DesktopNativeWidgetAura::OnHostResized(const aura::WindowTreeHost* host) {
 
   gfx::Rect new_bounds = gfx::Rect(host->window()->bounds().size());
   content_window_->SetBounds(new_bounds);
-  // Can be NULL at start.
-  if (content_window_container_)
-    content_window_container_->SetBounds(new_bounds);
   native_widget_delegate_->OnNativeWidgetSizeChanged(new_bounds.size());
 }