Aura: Allow compact window mode to be turned on/off at runtime

* In debug builds, Ctrl-Alt-A shows/hides it
* Added test coverage for switching modes
* Refactored Shell initialization to support this

BUG=110174
TEST=aura_shell_unittests ShellTest.ChangeWindowMode, manual toggling

Review URL: https://chromiumcodereview.appspot.com/9289008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@119111 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 6 insertions, 4 deletions

diff --git a/ash/wm/root_window_layout_manager.h b/ash/wm/root_window_layout_manager.h
index 79ac330..d5f4a0c 100644
--- a/ash/wm/root_window_layout_manager.h
+++ b/ash/wm/root_window_layout_manager.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 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.
 
@@ -30,9 +30,11 @@ class RootWindowLayoutManager : public aura::LayoutManager {
   explicit RootWindowLayoutManager(aura::Window* owner);
   virtual ~RootWindowLayoutManager();
 
-  void set_background_widget(views::Widget* background_widget) {
-    background_widget_ = background_widget;
-  }
+  views::Widget* background_widget() { return background_widget_; }
+
+  // Sets the background to |widget|. Closes and destroys the old widget if it
+  // exists and differs from the new widget.
+  void SetBackgroundWidget(views::Widget* widget);
 
   // Overridden from aura::LayoutManager:
   virtual void OnWindowResized() OVERRIDE;