Reduce usage of MessageLoopProxy in base/

base/test/launcher/test_launcher.cc

Index: base/test/launcher/test_launcher.cc
diff --git a/base/test/launcher/test_launcher.cc b/base/test/launcher/test_launcher.cc
index eab51f4aed839d95552ac543a09ccb3748939938..03cd54373fad06f6c5b7322f1caaba5f5a297cda 100644
--- a/base/test/launcher/test_launcher.cc
+++ b/base/test/launcher/test_launcher.cc
@@ -33,6 +33,7 @@
 #include "base/test/sequenced_worker_pool_owner.h"
 #include "base/test/test_switches.h"
 #include "base/test/test_timeouts.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/threading/thread_checker.h"
 #include "base/time/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -351,7 +352,7 @@ void DoLaunchChildTestProcess(
     base::TimeDelta timeout,
     int flags,
     bool redirect_stdio,
-    scoped_refptr<MessageLoopProxy> message_loop_proxy,
+    scoped_refptr<SequencedTaskRunner> task_runner,
     const TestLauncher::LaunchChildGTestProcessCallback& callback) {
   TimeTicks start_time = TimeTicks::Now();
 
@@ -422,14 +423,13 @@ void DoLaunchChildTestProcess(
 
   // Run target callback on the thread it was originating from, not on
   // a worker pool thread.
-  message_loop_proxy->PostTask(
-      FROM_HERE,
-      Bind(&RunCallback,
-           callback,
-           exit_code,
-           TimeTicks::Now() - start_time,
-           was_timeout,
-           output_file_contents));
+  task_runner->PostTask(FROM_HERE,
+                        Bind(&RunCallback,
+                             callback,
+                             exit_code,
+                             TimeTicks::Now() - start_time,
+                             was_timeout,
+                             output_file_contents));
 }
 
 }  // namespace
@@ -541,7 +541,7 @@ void TestLauncher::LaunchChildGTestProcess(
            timeout,
            flags,
            redirect_stdio,
-           MessageLoopProxy::current(),
+           ThreadTaskRunnerHandle::Get(),
            Bind(&TestLauncher::OnLaunchTestProcessFinished,
                 Unretained(this),
                 callback)));