Move stash_backend into extensions/browser/mojo.

extensions/browser/stash_backend.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 EXTENSIONS_BROWSER_STASH_BACKEND_H_
-#define EXTENSIONS_BROWSER_STASH_BACKEND_H_
-
-#include <vector>
-
-#include "base/memory/linked_ptr.h"
-#include "base/memory/weak_ptr.h"
-#include "extensions/common/stash.mojom.h"
-#include "mojo/public/cpp/bindings/interface_request.h"
-
-namespace extensions {
-
-// A backend that provides access to StashService for a single extension.
-class StashBackend {
- public:
-  StashBackend();
-  ~StashBackend();
-
-  // Creates a StashService that forwards calls to this StashBackend and bind it
-  // to |request|.
-  void BindToRequest(mojo::InterfaceRequest<StashService> request);
-
-  // Adds the StashedObjects contained within |stash| to the stash.
-  void AddToStash(mojo::Array<StashedObjectPtr> stash);
-
-  // Returns all StashedObjects added to the stash since the last call to
-  // RetrieveStash.
-  mojo::Array<StashedObjectPtr> RetrieveStash();
-
- private:
-  // The objects that have been stashed.
-  mojo::Array<StashedObjectPtr> stashed_objects_;
-
-  base::WeakPtrFactory<StashBackend> weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(StashBackend);
-};
-
-}  // namespace extensions
-
-#endif  // EXTENSIONS_BROWSER_STASH_BACKEND_H_