Fix a null ptr crash on a empty body response on mojo loading

content/child/resource_dispatcher.cc

 // 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.
 
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
 
 #include "content/child/resource_dispatcher.h"
 
 #include <utility>
 
@@ skipping 83 matching lines @@
   }
 
   void OnStartLoadingResponseBody(
       mojo::ScopedDataPipeConsumerHandle body) override {
     DCHECK(!body_consumer_);
     body_consumer_ = new URLResponseBodyConsumer(
         request_id_, resource_dispatcher_, std::move(body), task_runner_);
   }
 
   void OnComplete(const ResourceRequestCompletionStatus& status) override {
+    if (!body_consumer_) {
+      resource_dispatcher_->OnMessageReceived(
+          ResourceMsg_RequestComplete(request_id_, status));
+      return;
+    }
     body_consumer_->OnComplete(status);
   }
 
   mojom::URLLoaderClientPtr CreateInterfacePtrAndBind() {
     return binding_.CreateInterfacePtrAndBind();
   }
 
  private:
   mojo::Binding<mojom::URLLoaderClient> binding_;
   scoped_refptr<URLResponseBodyConsumer> body_consumer_;
@@ skipping 696 matching lines @@
     delete message;
   }
 }
 
 void ResourceDispatcher::SetResourceSchedulingFilter(
     scoped_refptr<ResourceSchedulingFilter> resource_scheduling_filter) {
   resource_scheduling_filter_ = resource_scheduling_filter;
 }
 
 }  // namespace content