Revert of Deletes mojo::Callback

mojo/public/cpp/bindings/associated_binding.h

 // Copyright 2015 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_ASSOCIATED_BINDING_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_ASSOCIATED_BINDING_H_
 
 #include <memory>
 #include <utility>
 
 #include "base/bind.h"
-#include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "mojo/public/cpp/bindings/associated_group.h"
 #include "mojo/public/cpp/bindings/associated_interface_request.h"
+#include "mojo/public/cpp/bindings/callback.h"
 #include "mojo/public/cpp/bindings/lib/interface_endpoint_client.h"
 #include "mojo/public/cpp/bindings/lib/multiplex_router.h"
 #include "mojo/public/cpp/bindings/scoped_interface_endpoint_handle.h"
 
 namespace mojo {
 
 // Represents the implementation side of an associated interface. It is similar
 // to Binding, except that it doesn't own a message pipe handle.
 //
 // When you bind this class to a request, optionally you can specify a
@@ skipping 100 matching lines @@
     connection_error_handler_.Reset();
 
     return request;
   }
 
   // Sets an error handler that will be called if a connection error occurs.
   //
   // This method may only be called after this AssociatedBinding has been bound
   // to a message pipe. The error handler will be reset when this
   // AssociatedBinding is unbound or closed.
-  void set_connection_error_handler(const base::Closure& error_handler) {
+  void set_connection_error_handler(const Closure& error_handler) {
     DCHECK(is_bound());
     connection_error_handler_ = error_handler;
   }
 
   // Returns the interface implementation that was previously specified.
   Interface* impl() { return impl_; }
 
   // Indicates whether the associated binding has been completed.
   bool is_bound() const { return !!endpoint_client_; }
 
   // Returns the associated group that this object belongs to. Returns null if
   // the object is not bound.
   AssociatedGroup* associated_group() {
     return endpoint_client_ ? endpoint_client_->associated_group() : nullptr;
   }
 
  private:
   void RunConnectionErrorHandler() {
     if (!connection_error_handler_.is_null())
       connection_error_handler_.Run();
   }
 
   std::unique_ptr<internal::InterfaceEndpointClient> endpoint_client_;
 
   typename Interface::Stub_ stub_;
   Interface* impl_;
-  base::Closure connection_error_handler_;
+  Closure connection_error_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(AssociatedBinding);
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_ASSOCIATED_BINDING_H_