Support early associated interface binding on ChannelMojo

mojo/public/cpp/bindings/lib/interface_endpoint_client.cc

 // 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.
 
 #include "mojo/public/cpp/bindings/interface_endpoint_client.h"
 
 #include <stdint.h>
 
 #include <utility>
 
@@ skipping 141 matching lines @@
 
   controller_ = handle_.group_controller()->AttachEndpointClient(
       handle_, this, task_runner_);
   if (expect_sync_requests)
     controller_->AllowWokenUpBySyncWatchOnSameThread();
 }
 
 InterfaceEndpointClient::~InterfaceEndpointClient() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
-  handle_.group_controller()->DetachEndpointClient(handle_);
+  if (handle_.is_valid())
+    handle_.group_controller()->DetachEndpointClient(handle_);
 }
 
 AssociatedGroup* InterfaceEndpointClient::associated_group() {
   if (!associated_group_)
     associated_group_ = handle_.group_controller()->CreateAssociatedGroup();
   return associated_group_.get();
 }
 
 uint32_t InterfaceEndpointClient::interface_id() const {
   DCHECK(thread_checker_.CalledOnValidThread());
@@ skipping 132 matching lines @@
     return responder->Accept(message);
   } else {
     if (!incoming_receiver_)
       return false;
 
     return incoming_receiver_->Accept(message);
   }
 }
 
 }  // namespace mojo