Add MediaServiceThrottler

media/base/android/media_server_crash_listener.cc

Index: media/base/android/media_server_crash_listener.cc
diff --git a/media/base/android/media_server_crash_listener.cc b/media/base/android/media_server_crash_listener.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3a3e5a161a695957e40f8e0f8efd8e7aac90233c
--- /dev/null
+++ b/media/base/android/media_server_crash_listener.cc
@@ -0,0 +1,63 @@
+// Copyright 2016 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 "media/base/android/media_server_crash_listener.h"
+
+#include "base/android/context_utils.h"
+#include "base/android/jni_android.h"
+#include "base/memory/singleton.h"
+#include "jni/MediaServerCrashListener_jni.h"
+
+namespace media {
+
+// static
+MediaServerCrashListener* MediaServerCrashListener::GetInstance() {
+  return base::Singleton<

[DaleCurtis, 2016/11/08 22:35:41]

Typically we use LazyInstance instead of a base::Singleton. I think it's
probably worth shutting this down when there haven't been any active listeners
for > x seconds.

[tguilbert, 2016/11/11 03:50:29]

Changed to have the lifetime managed by the MediaServiceThrottler.

+      MediaServerCrashListener,
+      base::LeakySingletonTraits<MediaServerCrashListener>>::get();
+}
+
+// static
+bool MediaServerCrashListener::RegisterMediaServerCrashListener(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+MediaServerCrashListener::~MediaServerCrashListener() {}
+
+void MediaServerCrashListener::SetOnServerCrashCallback(
+    const base::Closure& on_server_crash_cb,
+    scoped_refptr<base::SingleThreadTaskRunner> callback_thread) {

[DaleCurtis, 2016/11/08 22:35:41]

Unless you're using std::move() this should probably still be const&. I forget
the latest rules though.

[tguilbert, 2016/11/11 03:50:29]

By value or std::move() is the latest.

https://chromium.googlesource.com/chromium/src/+/master/styleguide/c++/c++.md...

+  // There is currently only one client of MediaServerCrashListener. A more
+  // robust observer/callback mechanism should be implemented if that changed.
+  DCHECK(!on_server_crash_cb_);
+  on_server_crash_cb_ = on_server_crash_cb;
+  callback_task_runner_ = callback_thread;
+}
+
+void MediaServerCrashListener::OnMediaServerCrashDetected(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& obj) {
+  if (on_server_crash_cb_)
+    callback_task_runner_->PostTask(FROM_HERE, on_server_crash_cb_);
+}
+
+void MediaServerCrashListener::ClearOnServerCrashCallbackForTesting() {
+  on_server_crash_cb_.Reset();
+}
+
+bool MediaServerCrashListener::StartListening() {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  return Java_MediaServerCrashListener_startListening(env, j_crash_listener_);
+}
+
+MediaServerCrashListener::MediaServerCrashListener() {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  CHECK(env);
+
+  j_crash_listener_.Reset(Java_MediaServerCrashListener_create(
+      env, base::android::GetApplicationContext(),
+      reinterpret_cast<intptr_t>(this)));
+}
+
+}  // namespace media