Rewrite scoped_ptr<T>(NULL) to use the default ctor in ash/.

ash/wm/workspace/workspace_cycler_animator.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/wm/workspace/workspace_cycler_animator.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "ash/launcher/launcher.h"
@@ skipping 344 matching lines @@
       Config::SHALLOWER_THAN_SELECTED_Y_OFFSETS);
   // Hide workspaces for which there is no y offset specified.
   return y_offsets.GetSize();
 }
 
 WorkspaceCyclerAnimator::WorkspaceCyclerAnimator(Delegate* delegate)
     : delegate_(delegate),
       initial_active_workspace_index_(0),
       selected_workspace_index_(0),
       scroll_delta_(0),
-      animation_type_(NONE),
-      launcher_background_controller_(NULL),
-      style_calculator_(NULL) {
-}
+      animation_type_(NONE) {}
 
 WorkspaceCyclerAnimator::~WorkspaceCyclerAnimator() {
   StopObservingImplicitAnimations();
   animation_type_ = NONE;
 }
 
 void WorkspaceCyclerAnimator::Init(const std::vector<Workspace*>& workspaces,
                                    Workspace* initial_active_workspace) {
   workspaces_ = workspaces;
 
@@ skipping 349 matching lines @@
     base::MessageLoopForUI::current()->PostTask(
         FROM_HERE,
         base::Bind(&WorkspaceCyclerAnimator::NotifyDelegate,
                    AsWeakPtr(),
                    completed_animation));
   }
 }
 
 }  // namespace internal
 }  // namespace ash