Replace MessageLoop::current()->task_runner() with ThreadTaskRunnerHandle::Get().

services/shell/standalone/tracer.cc

 // Copyright 2015 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 "services/shell/standalone/tracer.h"
 
 #include <stddef.h>
 #include <stdio.h>
 #include <string.h>
 #include <utility>
 
 #include "base/message_loop/message_loop.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/threading/thread.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "base/trace_event/trace_config.h"
 #include "base/trace_event/trace_event.h"
 
 namespace shell {
 
 Tracer::Tracer()
     : tracing_(false), first_chunk_written_(false), trace_file_(nullptr) {}
 
 Tracer::~Tracer() {
   StopAndFlushToFile();
 }
 
 void Tracer::Start(const std::string& categories,
                    const std::string& duration_seconds_str,
                    const std::string& filename) {
   tracing_ = true;
   trace_filename_ = filename;
   categories_ = categories;
   base::trace_event::TraceConfig config(categories,
                                         base::trace_event::RECORD_UNTIL_FULL);
   base::trace_event::TraceLog::GetInstance()->SetEnabled(
       config, base::trace_event::TraceLog::RECORDING_MODE);
 
   int trace_duration_secs = 5;
   if (!duration_seconds_str.empty()) {
     CHECK(base::StringToInt(duration_seconds_str, &trace_duration_secs))
         << "Could not parse --trace-startup-duration value "
         << duration_seconds_str;
   }
-  base::MessageLoop::current()->task_runner()->PostDelayedTask(
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
       FROM_HERE,
       base::Bind(&Tracer::StopAndFlushToFile, base::Unretained(this)),
       base::TimeDelta::FromSeconds(trace_duration_secs));
 }
 
 void Tracer::StartCollectingFromTracingService(
     tracing::mojom::CollectorPtr coordinator) {
   coordinator_ = std::move(coordinator);
   mojo::DataPipe data_pipe;
   coordinator_->Start(std::move(data_pipe.producer_handle), categories_);
@@ skipping 98 matching lines @@
   WriteFooterAndClose();
 }
 
 void Tracer::WriteCommaIfNeeded() {
   if (first_chunk_written_)
     PCHECK(fwrite(",", 1, 1, trace_file_) == 1);
   first_chunk_written_ = true;
 }
 
 }  // namespace shell