Disallowing shelf changes via drag & drop if the enterprise profile does not allow changes

ash/launcher/launcher_delegate.h

 // 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.
 
 #ifndef ASH_LAUNCHER_LAUNCHER_DELEGATE_H_
 #define ASH_LAUNCHER_LAUNCHER_DELEGATE_H_
 
 #include "ash/ash_export.h"
 #include "ash/launcher/launcher_types.h"
 
@@ skipping 27 matching lines @@
   virtual const std::string& GetAppIDForLauncherID(LauncherID id) = 0;
 
   // Pins an app with |app_id| to launcher. A running instance will get pinned.
   // In case there is no running instance a new launcher item is created and
   // pinned.
   virtual void PinAppWithID(const std::string& app_id) = 0;
 
   // Check if the app with |app_id_| is pinned to the launcher.
   virtual bool IsAppPinned(const std::string& app_id) = 0;
 
+  // Checks whether the user is allowed to pin/unpin apps. Pinning may be
+  // disallowed by policy in case there is a pre-defined set of pinned apps.
+  virtual bool CanPin() const = 0;
+
   // Unpins app item with |app_id|.
   virtual void UnpinAppWithID(const std::string& app_id) = 0;
 };
 
 }  // namespace ash
 
 #endif  // ASH_LAUNCHER_LAUNCHER_DELEGATE_H_