Use ThreadTaskRunnerHandle instead of MessageLoop::current() in base/.

base/trace_event/memory_dump_manager.cc

Index: base/trace_event/memory_dump_manager.cc
diff --git a/base/trace_event/memory_dump_manager.cc b/base/trace_event/memory_dump_manager.cc
index c37bf5bf5003ebcfd559279b66f1bdefb815fac2..d139454a1e85630454f519637c78a2f331e22cb6 100644
--- a/base/trace_event/memory_dump_manager.cc
+++ b/base/trace_event/memory_dump_manager.cc
@@ -756,7 +756,7 @@ MemoryDumpManager::ProcessMemoryDumpAsyncState::ProcessMemoryDumpAsyncState(
       session_state(std::move(session_state)),
       callback(callback),
       dump_successful(true),
-      callback_task_runner(MessageLoop::current()->task_runner()),
+      callback_task_runner(ThreadTaskRunnerHandle::Get()),
       dump_thread_task_runner(std::move(dump_thread_task_runner)) {
   pending_dump_providers.reserve(dump_providers.size());
   pending_dump_providers.assign(dump_providers.rbegin(), dump_providers.rend());