android: Java-based launcher thread

content/browser/android/launcher_thread.h

+// Copyright 2017 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 "base/android/java_handler_thread.h"
+
+#include "base/lazy_instance.h"
+
+namespace base {
+class MessageLoop;
+}
+
+namespace content {
+namespace android {
+
+// This is Android's launcher thread. This should not be used directly in
+// native code, but accessed through BrowserThread(Impl) instead.
+class LauncherThread {
+ public:
+  static base::MessageLoop* GetMessageLoop();
+
+ private:
+  friend base::LazyInstanceTraitsBase<LauncherThread>;
+
+  LauncherThread();
+  ~LauncherThread();
+
+  base::android::JavaHandlerThread java_handler_thread_;
+};
+
+}  // namespace android
+}  // namespace content