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

ash/wm/workspace/workspace_cycler_animator.cc

Index: ash/wm/workspace/workspace_cycler_animator.cc
diff --git a/ash/wm/workspace/workspace_cycler_animator.cc b/ash/wm/workspace/workspace_cycler_animator.cc
index 1a0c3c3e05861aabc7c8937327b9d865d5990ed4..1d6f775f5632fb9dccbc0995ebe82850c56059e0 100644
--- a/ash/wm/workspace/workspace_cycler_animator.cc
+++ b/ash/wm/workspace/workspace_cycler_animator.cc
@@ -362,10 +362,7 @@ WorkspaceCyclerAnimator::WorkspaceCyclerAnimator(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();