Revert of Deletes mojo::Callback

mojo/public/cpp/bindings/strong_binding.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 MOJO_PUBLIC_CPP_BINDINGS_STRONG_BINDING_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_STRONG_BINDING_H_
 
 #include <utility>
 
 #include "base/bind.h"
-#include "base/callback.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "mojo/public/cpp/bindings/binding.h"
+#include "mojo/public/cpp/bindings/callback.h"
 #include "mojo/public/cpp/bindings/interface_ptr.h"
 #include "mojo/public/cpp/bindings/interface_request.h"
 #include "mojo/public/cpp/bindings/lib/filter_chain.h"
 #include "mojo/public/cpp/bindings/lib/message_header_validator.h"
 #include "mojo/public/cpp/bindings/lib/router.h"
 #include "mojo/public/cpp/system/core.h"
 
 namespace mojo {
 
 // This connects an interface implementation strongly to a pipe. When a
@@ skipping 67 matching lines @@
   }
 
   bool WaitForIncomingMethodCall() {
     return binding_.WaitForIncomingMethodCall();
   }
 
   // Note: The error handler must not delete the interface implementation.
   //
   // This method may only be called after this StrongBinding has been bound to a
   // message pipe.
-  void set_connection_error_handler(const base::Closure& error_handler) {
+  void set_connection_error_handler(const Closure& error_handler) {
     DCHECK(binding_.is_bound());
     connection_error_handler_ = error_handler;
   }
 
   Interface* impl() { return binding_.impl(); }
   // Exposed for testing, should not generally be used.
   internal::Router* internal_router() { return binding_.internal_router(); }
 
   void OnConnectionError() {
     if (!connection_error_handler_.is_null())
       connection_error_handler_.Run();
     delete binding_.impl();
   }
 
  private:
-  base::Closure connection_error_handler_;
+  Closure connection_error_handler_;
   Binding<Interface> binding_;
 
   DISALLOW_COPY_AND_ASSIGN(StrongBinding);
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_STRONG_BINDING_H_