Revert "content: Remove use of MessageLoopProxy and deprecated MessageLoop APIs"

content/test/test_blink_web_unit_test_support.cc

Index: content/test/test_blink_web_unit_test_support.cc
diff --git a/content/test/test_blink_web_unit_test_support.cc b/content/test/test_blink_web_unit_test_support.cc
index 444272ea88dccbc30f27ab30c60f7a6938ffc101..05a6b9bcce2fec1c48d896fbe7d74c177ba377f5 100644
--- a/content/test/test_blink_web_unit_test_support.cc
+++ b/content/test/test_blink_web_unit_test_support.cc
@@ -95,7 +95,7 @@ TestBlinkWebUnitTestSupport::TestBlinkWebUnitTestSupport() {
 
   scoped_refptr<base::SingleThreadTaskRunner> dummy_task_runner;
   scoped_ptr<base::ThreadTaskRunnerHandle> dummy_task_runner_handle;
-  if (!base::ThreadTaskRunnerHandle::IsSet()) {
+  if (!base::MessageLoopProxy::current()) {
     // Dummy task runner is initialized here because the blink::initialize
     // creates IsolateHolder which needs the current task runner handle. There
     // should be no task posted to this task runner. The message loop is not