Relanding "Add apk for running content_browsertests"

base/test/test_support_android.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 <stdarg.h>
 #include <string.h>
 
 #include "base/android/path_utils.h"
 #include "base/file_path.h"
 #include "base/logging.h"
@@ skipping 165 matching lines @@
                        false,    // Timestamp
                        false);   // Tick count
 }
 
 void InitAndroidTestPaths() {
   InitPathProvider(DIR_MODULE);
   InitPathProvider(DIR_ANDROID_APP_DATA);
 }
 
 void InitAndroidTestMessageLoop() {
-  MessageLoop::InitMessagePumpForUIFactory(&CreateMessagePumpForUIStub);
+  if (!MessageLoop::InitMessagePumpForUIFactory(&CreateMessagePumpForUIStub))
+    LOG(INFO) << "MessagePumpForUIFactory already set, unable to override.";
 }
 
 void InitAndroidTest() {
   InitAndroidTestLogging();
   InitAndroidTestPaths();
   InitAndroidTestMessageLoop();
 }
 }  // namespace base