Fixes three crashes

athena/main/athena_main.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 "athena/content/public/web_contents_view_delegate_creator.h"
 #include "athena/main/athena_app_window_controller.h"
 #include "athena/main/athena_launcher.h"
 #include "athena/screen/public/screen_manager.h"
 #include "athena/screen/public/screen_manager_delegate.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/path_service.h"
 #include "content/public/app/content_main.h"
+#include "content/public/browser/browser_thread.h"
 #include "extensions/shell/app/shell_main_delegate.h"
 #include "extensions/shell/browser/shell_browser_main_delegate.h"
 #include "extensions/shell/browser/shell_content_browser_client.h"
 #include "extensions/shell/browser/shell_desktop_controller.h"
 #include "extensions/shell/browser/shell_extension_system.h"
 #include "extensions/shell/common/switches.h"
 #include "ui/aura/window_tree_host.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/wm/core/visibility_controller.h"
 
@@ skipping 63 matching lines @@
           static_cast<extensions::ShellExtensionSystem*>(
               extensions::ExtensionSystem::Get(context));
       extension_system->LoadApp(app_absolute_dir);
     }
 
     extensions::ShellDesktopController* desktop_controller =
         extensions::ShellDesktopController::instance();
     screen_manager_delegate_.reset(
         new AthenaScreenManagerDelegate(desktop_controller));
     athena::StartAthenaEnv(desktop_controller->host()->window(),
-                           screen_manager_delegate_.get());
+                           screen_manager_delegate_.get(),
+                           content::BrowserThread::GetMessageLoopProxyForThread(
+                               content::BrowserThread::FILE));
     athena::StartAthenaSessionWithContext(context);
   }
 
   virtual void Shutdown() OVERRIDE {
     athena::ShutdownAthena();
   }
 
   virtual extensions::ShellDesktopController* CreateDesktopController()
       OVERRIDE {
     // TODO(mukai): create Athena's own ShellDesktopController subclass so that
@@ skipping 52 matching lines @@
 
 int main(int argc, const char** argv) {
   AthenaMainDelegate delegate;
   content::ContentMainParams params(&delegate);
 
   params.argc = argc;
   params.argv = argv;
 
   return content::ContentMain(params);
 }