Remove use of deprecated MessageLoop methods in mojo.

mojo/android/system/core_impl.cc

 // Copyright 2014 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 "mojo/android/system/core_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
 
 #include "base/android/base_jni_registrar.h"
 #include "base/android/jni_android.h"
 #include "base/android/jni_registrar.h"
 #include "base/android/library_loader/library_loader_hooks.h"
 #include "base/android/scoped_java_ref.h"
 #include "base/bind.h"
-#include "base/message_loop/message_loop.h"
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "jni/CoreImpl_jni.h"
 #include "mojo/message_pump/handle_watcher.h"
 #include "mojo/public/c/system/core.h"
 
 namespace {
 
 using MojoAsyncWaitID = uintptr_t;
 const MojoAsyncWaitID kInvalidHandleCancelID = 0;
 
 struct AsyncWaitCallbackData {
@@ skipping 345 matching lines @@
       new AsyncWaitCallbackData(env, jcaller, callback);
   MojoAsyncWaitID cancel_id;
   if (static_cast<MojoHandle>(mojo_handle) != MOJO_HANDLE_INVALID) {
     common::HandleWatcher* watcher = new common::HandleWatcher();
     cancel_id = reinterpret_cast<MojoAsyncWaitID>(watcher);
     watcher->Start(Handle(static_cast<MojoHandle>(mojo_handle)), signals,
                    deadline,
                    base::Bind(&AsyncWaitCallback, watcher, callback_data));
   } else {
     cancel_id = kInvalidHandleCancelID;
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&AsyncWaitCallback, nullptr, callback_data,
                               MOJO_RESULT_INVALID_ARGUMENT));
   }
   base::android::ScopedJavaLocalRef<jobject> cancellable =
       Java_CoreImpl_newAsyncWaiterCancellableImpl(
           env, jcaller, cancel_id, reinterpret_cast<intptr_t>(callback_data));
   callback_data->cancellable.Reset(env, cancellable.obj());
   return cancellable;
 }
 
@@ skipping 24 matching lines @@
     return 0;
   return alignment - offset;
 }
 
 bool RegisterCoreImpl(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace android
 }  // namespace mojo