Remove MOJO_SHELL_CLIENT define.

chrome/test/base/browser_tests_main.cc

 // Copyright 2013 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 <algorithm>
 
 #include "base/sys_info.h"
 #include "chrome/test/base/chrome_test_launcher.h"
 #include "chrome/test/base/chrome_test_suite.h"
 
-#if defined(MOJO_SHELL_CLIENT)
+#if defined(USE_AURA)
 #include "chrome/test/base/mash_browser_tests_main.h"
 #endif
 
 int main(int argc, char** argv) {
-#if defined(MOJO_SHELL_CLIENT)
+#if defined(USE_AURA)
   int exit_code = 0;
   if (RunMashBrowserTests(argc, argv, &exit_code))
     return exit_code;
 #endif
 
   int default_jobs = std::max(1, base::SysInfo::NumberOfProcessors() / 2);
   ChromeTestSuiteRunner runner;
   ChromeTestLauncherDelegate delegate(&runner);
   return LaunchChromeTests(default_jobs, &delegate, argc, argv);
 }