Ensure queued Channel messages are flushed for in-process renderers

content/browser/renderer_host/render_process_host_impl.cc

 // Copyright 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.
 
 // Represents the browser side of the browser <--> renderer communication
 // channel. There will be one RenderProcessHost per renderer process.
 
 #include "content/browser/renderer_host/render_process_host_impl.h"
 
 #include <algorithm>
@@ skipping 878 matching lines @@
     // As for execution sequence, this callback should have no any dependency
     // on starting in-process-render-thread.
     // So put it here to trigger ChannelMojo initialization earlier to enable
     // in-process-render-thread using ChannelMojo there.
     OnProcessLaunched();  // Fake a callback that the process is ready.
 
     in_process_renderer_->StartWithOptions(options);
 
     g_in_process_thread = in_process_renderer_->message_loop();
 
+    // Make sure any queued messages on the channel are flushed in the case
+    // where we aren't launching a child process.
+    channel_->Flush();
   } else {
     // Build command line for renderer.  We call AppendRendererCommandLine()
     // first so the process type argument will appear first.
     base::CommandLine* cmd_line = new base::CommandLine(renderer_path);
     if (!renderer_prefix.empty())
       cmd_line->PrependWrapper(renderer_prefix);
     AppendRendererCommandLine(cmd_line);
 
     // Spawn the child process asynchronously to avoid blocking the UI thread.
     // As long as there's no renderer prefix, we can use the zygote process
@@ skipping 2096 matching lines @@
   bad_message::ReceivedBadMessage(render_process_id,
                                   bad_message::RPH_MOJO_PROCESS_ERROR);
 }
 
 void RenderProcessHostImpl::CreateURLLoaderFactory(
     mojo::InterfaceRequest<mojom::URLLoaderFactory> request) {
   URLLoaderFactoryImpl::Create(resource_message_filter_, std::move(request));
 }
 
 }  // namespace content