Use thread with looper and native message loop for vsync service.

shell/android/android_handler.h

Index: shell/android/android_handler.h
diff --git a/shell/android/android_handler.h b/shell/android/android_handler.h
index 468d82494a9c229d68197ea080f0aea39e8dea6c..12bba7227ec2562ad89b3381f8b5f7883e03ee76 100644
--- a/shell/android/android_handler.h
+++ b/shell/android/android_handler.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef MOJO_SHELL_ANDROID_CONTENT_HANDLER_H_
-#define MOJO_SHELL_ANDROID_CONTENT_HANDLER_H_
+#ifndef SHELL_ANDROID_ANDROID_HANDLER_H_
+#define SHELL_ANDROID_ANDROID_HANDLER_H_
 
 #include <jni.h>
 
@@ -53,4 +53,4 @@ bool RegisterAndroidHandlerJni(JNIEnv* env);
 
 }  // namespace shell
 
-#endif  // MOJO_SHELL_ANDROID_CONTENT_HANDLER_H_
+#endif  // SHELL_ANDROID_ANDROID_HANDLER_H_