Enable wallpaper boot animation for boot into sign in too. Add flag to disable it.

ash/shell.cc

 // 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.
 
 #include "ash/shell.h"
 
 #include <algorithm>
 #include <string>
 
 #include "ash/accelerators/focus_manager_factory.h"
@@ skipping 120 matching lines @@
   virtual void OpenSetWallpaperPage() OVERRIDE {
   }
 
   virtual bool CanOpenSetWallpaperPage() OVERRIDE {
     return false;
   }
 
   virtual void OnWallpaperAnimationFinished() OVERRIDE {
   }
 
+  virtual void OnWallpaperBootAnimationFinished() OVERRIDE {
+  }
+
  private:
   DISALLOW_COPY_AND_ASSIGN(DummyUserWallpaperDelegate);
 };
 
 }  // namespace
 
 // static
 Shell* Shell::instance_ = NULL;
 // static
 bool Shell::initially_hide_cursor_ = false;
@@ skipping 636 matching lines @@
 }
 
 void Shell::ShowCursor(bool visible) {
   RootWindowList root_windows = GetAllRootWindows();
   for (RootWindowList::iterator iter = root_windows.begin();
        iter != root_windows.end(); ++iter)
     (*iter)->ShowCursor(visible);
 }
 
 }  // namespace ash