Remove use of deprecated MessageLoop methods in components.

components/safe_json/testing_json_parser.cc

Index: components/safe_json/testing_json_parser.cc
diff --git a/components/safe_json/testing_json_parser.cc b/components/safe_json/testing_json_parser.cc
index ec24bc90707126312224b1a461bb7d9ccfd51db7..c2f9639ab6bdceb2f0e0f15a7d44223c295a3ed3 100644
--- a/components/safe_json/testing_json_parser.cc
+++ b/components/safe_json/testing_json_parser.cc
@@ -10,7 +10,8 @@
 #include "base/bind_helpers.h"
 #include "base/json/json_reader.h"
 #include "base/location.h"
-#include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "base/values.h"
 
 namespace safe_json {
@@ -51,8 +52,8 @@ void TestingJsonParser::Start() {
 
   // Run the callback asynchronously. Post the delete task first, so that the
   // completion callbacks may quit the run loop without leaking |this|.
-  base::MessageLoop::current()->DeleteSoon(FROM_HERE, this);
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE, this);
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, value ? base::Bind(success_callback_, base::Passed(&value))
                        : base::Bind(error_callback_, error));
 }