Adding a gray semi transparent backdrop behind the topmost window within the default container

chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc

 // Copyright 2013 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 "chrome/browser/ui/ash/launcher/chrome_launcher_controller.h"
 
 #include <vector>
 
 #include "ash/ash_switches.h"
 #include "ash/desktop_background/desktop_background_controller.h"
@@ skipping 541 matching lines @@
   if (index < 0)
     return false;
   ash::ShelfItemType type = model_->items()[index].type;
   return (type == ash::TYPE_APP_SHORTCUT || type == ash::TYPE_BROWSER_SHORTCUT);
 }
 
 void ChromeLauncherController::TogglePinned(ash::ShelfID id) {
   if (!HasItemController(id))
     return;  // May happen if item closed with menu open.
 
+  // Added for temporary test purposes.
+  // TODO(skuhne): Remove this!
+  if (true) {
+    ash::Shell* shell = ash::Shell::GetInstance();
+    shell->EnableMaximizeModeWindowManager(
+        !shell->IsMaximizeModeWindowManagerEnabled());
+    return;
+  }
+
   if (IsPinned(id))
     Unpin(id);
   else
     Pin(id);
 }
 
 bool ChromeLauncherController::IsPinnable(ash::ShelfID id) const {
   int index = model_->ItemIndexByID(id);
   if (index == -1)
     return false;
@@ skipping 1486 matching lines @@
 }
 
 void ChromeLauncherController::ReleaseProfile() {
   if (app_sync_ui_state_)
     app_sync_ui_state_->RemoveObserver(this);
 
   PrefServiceSyncable::FromProfile(profile_)->RemoveObserver(this);
 
   pref_change_registrar_.RemoveAll();
 }