Launch browser when --memlog is specified on the command line.

chrome/profiling/profiling_globals.cc

+// Copyright 2017 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 "chrome/profiling/profiling_globals.h"
+
+#include "base/memory/ptr_util.h"
+#include "base/message_loop/message_loop.h"
+#include "base/threading/thread.h"
+#include "build/build_config.h"
+
+namespace profiling {
+
+ProfilingGlobals::ProfilingGlobals()
+    : io_thread_(base::MakeUnique<base::Thread>("IO thread")) {

[awong, 2017/06/14 23:15:19]

Don't change this code, but do we actually want an I/O thread in the future?

Or can we just use one message loop such that the UI thread *is* an IO thread?


Also, why is this a unique_ptr<>?  Can't we just contain the base::Thread
directly?

[brettw, 2017/06/14 23:23:55]

I changed it. I did it that way because I was thinking we would want to control
the lifetime of the thread more precisely.

I added a note about changing the main thread to be the I/O thread in the
future. Not sure what we'll do with the main thread yet.

+#if defined(OS_WIN)
+  io_thread_->init_com_with_mta(true);
+#endif
+  base::Thread::Options options;
+  options.message_loop_type = base::MessageLoop::TYPE_IO;
+  io_thread_->StartWithOptions(options);
+}
+
+ProfilingGlobals::~ProfilingGlobals() {}
+
+// static
+ProfilingGlobals* ProfilingGlobals::Get() {
+  static ProfilingGlobals singleton;
+  return &singleton;
+}
+
+base::TaskRunner* ProfilingGlobals::GetIORunner() {
+  return io_thread_->task_runner().get();
+}
+
+scoped_refptr<base::SingleThreadTaskRunner> ProfilingGlobals::GetMainThread()
+    const {
+  CHECK(base::MessageLoop::current() == main_message_loop_);
+  return main_message_loop_->task_runner();
+}
+
+void ProfilingGlobals::RunMainMessageLoop() {
+  base::MessageLoopForUI message_loop;
+  DCHECK(!main_message_loop_);
+  main_message_loop_ = &message_loop;
+
+  base::RunLoop run_loop;
+  run_loop.Run();
+
+  main_message_loop_ = nullptr;
+}
+
+void ProfilingGlobals::QuitWhenIdle() {
+  main_message_loop_->QuitWhenIdle();
+}
+
+}  // namespace profiling