Fix the window not coming up sometimes on Windows when using --enable-multiprocess.

mojo/shell/child_process_host.cc

 // 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.
 
 #include "mojo/shell/child_process_host.h"
 
 #include "base/base_switches.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/location.h"
@@ skipping 104 matching lines @@
     if (apps_to_debug.empty() || ContainsValue(apps_to_debug, name_))
       child_command_line.AppendSwitch(switches::kWaitForDebugger);
   }
 
   embedder::HandlePassingInformation handle_passing_info;
   platform_channel_pair_.PrepareToPassClientHandleToChildProcess(
       &child_command_line, &handle_passing_info);
 
   base::LaunchOptions options;
 #if defined(OS_WIN)
-  options.start_hidden = true;
   options.handles_to_inherit = &handle_passing_info;
 #elif defined(OS_POSIX)
   options.fds_to_remap = &handle_passing_info;
 #endif
   DVLOG(2) << "Launching child with command line: "
            << child_command_line.GetCommandLineString();
   child_process_ = base::LaunchProcess(child_command_line, options);
   if (!child_process_.IsValid())
     return false;
 
@@ skipping 11 matching lines @@
 
 void ChildProcessHost::DidCreateChannel(embedder::ChannelInfo* channel_info) {
   DVLOG(2) << "AppChildProcessHost::DidCreateChannel()";
 
   CHECK(channel_info);
   channel_info_ = channel_info;
 }
 
 }  // namespace shell
 }  // namespace mojo