Rename wm_core_export.h to wm_export.h and the wm_core target to just wm

ui/wm/core/user_activity_observer.h

 // Copyright 2014 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.
 
 #ifndef UI_WM_CORE_USER_ACTIVITY_OBSERVER_H_
 #define UI_WM_CORE_USER_ACTIVITY_OBSERVER_H_
 
 #include "base/basictypes.h"
-#include "ui/wm/core/wm_core_export.h"
+#include "ui/wm/wm_export.h"
 
 namespace ui {
 class Event;
 }
 
 namespace wm {
 
 // Interface for classes that want to be notified about user activity.
 // Implementations should register themselves with UserActivityDetector.
-class WM_CORE_EXPORT UserActivityObserver {
+class WM_EXPORT UserActivityObserver {
  public:
   // Invoked periodically while the user is active (i.e. generating input
   // events). |event| is the event that triggered the notification; it may
   // be NULL in some cases (e.g. testing or synthetic invocations).
   virtual void OnUserActivity(const ui::Event* event) = 0;
 
  protected:
   UserActivityObserver() {}
   virtual ~UserActivityObserver() {}
 
   DISALLOW_COPY_AND_ASSIGN(UserActivityObserver);
 };
 
 }  // namespace wm
 
 #endif  // UI_WM_CORE_USER_ACTIVITY_OBSERVER_H_