media: Migrate media server crash callback.

According to the documentation, this is a repeating callback, called every time the media server crashes:
* https://cs.chromium.org/chromium/src/media/base/android/media_server_crash_listener.h?rcl=06d998f53ecbf18ef4512d8a22f1261ee4ab8c71&l=18
* https://cs.chromium.org/chromium/src/media/base/android/media_server_crash_listener.h?rcl=06d998f53ecbf18ef4512d8a22f1261ee4ab8c71&l=27
* https://cs.chromium.org/chromium/src/media/base/android/media_server_crash_listener.h?rcl=06d998f53ecbf18ef4512d8a22f1261ee4ab8c71&l=38

This is part of the base::Callback migration.

Context: https://cs.chromium.org/chromium/src/docs/callback.md?rcl=9fcc3764aea8f97e9f6de4a9ee61d554e67edcda&l=40

Bug: 714018
Change-Id: I871e908c72a6fc016faa2317bea51ece2e0da947
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2047247
Commit-Queue: Jose Lopes <jabolopes@google.com>
Reviewed-by: Xiaohan Wang <xhwang@chromium.org>
Reviewed-by: danakj <danakj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#743493}

media/base/android/media_server_crash_listener.cc

@@ -11,9 +11,9 @@
 namespace media {
 
 MediaServerCrashListener::MediaServerCrashListener(
-    const OnMediaServerCrashCB& on_server_crash_cb,
+    OnMediaServerCrashCB on_server_crash_cb,
     scoped_refptr<base::SingleThreadTaskRunner> callback_thread)
-    : on_server_crash_cb_(on_server_crash_cb),
+    : on_server_crash_cb_(std::move(on_server_crash_cb)),
       callback_task_runner_(std::move(callback_thread)) {
   JNIEnv* env = base::android::AttachCurrentThread();
   CHECK(env);

media/base/android/media_server_crash_listener.h

@@ -22,12 +22,12 @@ namespace media {
 // be more than a single instance of this class per process.
 class MediaServerCrashListener {
  public:
-  using OnMediaServerCrashCB = base::Callback<void(bool)>;
+  using OnMediaServerCrashCB = base::RepeatingCallback<void(bool)>;
 
   // Basic constructor. |on_server_crash_cb| will be posted to
-  // |callback_task_runner| everytime the watchdog MediaPlayer detects a crash.
+  // |callback_task_runner| every time the watchdog MediaPlayer detects a crash.
   MediaServerCrashListener(
-      const OnMediaServerCrashCB& on_server_crash_cb,
+      OnMediaServerCrashCB on_server_crash_cb,
       scoped_refptr<base::SingleThreadTaskRunner> callback_task_runner);
   ~MediaServerCrashListener();
 

media/base/android/media_service_throttler.cc

@@ -7,6 +7,7 @@
 #include <memory>
 
 #include "base/bind.h"
+#include "base/bind_helpers.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/default_tick_clock.h"
 #include "media/base/android/media_server_crash_listener.h"
@@ -197,7 +198,7 @@ void MediaServiceThrottler::EnsureCrashListenerStarted() {
     // base::Unretained is safe here because the MediaServiceThrottler will live
     // until the process is terminated.
     crash_listener_ = std::make_unique<MediaServerCrashListener>(
-        base::Bind(&MediaServiceThrottler::OnMediaServerCrash,
+        base::BindRepeating(&MediaServiceThrottler::OnMediaServerCrash,
                             base::Unretained(this)),
         crash_listener_task_runner_);
   } else {
@@ -225,8 +226,7 @@ void MediaServiceThrottler::SetCrashListenerTaskRunnerForTesting(
 
   // Re-create the crash listener.
   crash_listener_ = std::make_unique<MediaServerCrashListener>(
-      MediaServerCrashListener::OnMediaServerCrashCB(),
-      crash_listener_task_runner_);
+      base::NullCallback(), crash_listener_task_runner_);
 }
 
 }  // namespace media