Revert 186925 since it breaks many of the builds on the bots (e.g.

chrome/test/ppapi/ppapi_browsertest.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.
 
 #include "chrome/test/ppapi/ppapi_test.h"
 
 #include "base/test/test_timeouts.h"
 #include "build/build_config.h"
 #include "chrome/browser/content_settings/host_content_settings_map.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 1191 matching lines @@
 TEST_PPAPI_IN_PROCESS(MouseCursor)
 TEST_PPAPI_OUT_OF_PROCESS(MouseCursor)
 TEST_PPAPI_NACL(MouseCursor)
 
 // PPB_Printing only implemented for out of process.
 TEST_PPAPI_OUT_OF_PROCESS(Printing)
 
 // PPB_MessageLoop is only supported out-of-process.
 // TODO(dmichael): Enable for NaCl with the IPC proxy. crbug.com/116317
 TEST_PPAPI_OUT_OF_PROCESS(MessageLoop_Basics)
+// MessageLoop_Post starts a thread so only run it if pepper threads are
+// enabled.
+#ifdef ENABLE_PEPPER_THREADING
 TEST_PPAPI_OUT_OF_PROCESS(MessageLoop_Post)
+#endif
 
 // Going forward, Flash APIs will only work out-of-process.
 TEST_PPAPI_OUT_OF_PROCESS(Flash_GetLocalTimeZoneOffset)
 TEST_PPAPI_OUT_OF_PROCESS(Flash_GetProxyForURL)
 TEST_PPAPI_OUT_OF_PROCESS(Flash_GetSetting)
 TEST_PPAPI_OUT_OF_PROCESS(Flash_SetCrashData)
 // http://crbug.com/176822
 #if !defined(OS_WIN)
 TEST_PPAPI_OUT_OF_PROCESS(FlashClipboard)
 #endif
 TEST_PPAPI_OUT_OF_PROCESS(FlashFile)
 // Mac/Aura reach NOTIMPLEMENTED/time out.
 // mac: http://crbug.com/96767
 // aura: http://crbug.com/104384
 #if defined(OS_MACOSX)
 #define MAYBE_FlashFullscreen DISABLED_FlashFullscreen
 #else
 #define MAYBE_FlashFullscreen FlashFullscreen
 #endif
 TEST_PPAPI_OUT_OF_PROCESS(MAYBE_FlashFullscreen)
 
 TEST_PPAPI_IN_PROCESS(TalkPrivate)
 TEST_PPAPI_OUT_OF_PROCESS(TalkPrivate)
 
 #endif // ADDRESS_SANITIZER