base: Use std::move() instead of Pass() for real movable types.

base/test/thread_test_helper.cc

Index: base/test/thread_test_helper.cc
diff --git a/base/test/thread_test_helper.cc b/base/test/thread_test_helper.cc
index 6a12190898fab773d9c481df7b9b65ad20a0236f..f238cee43bccccee48a26c2ac4dc2a5de212566c 100644
--- a/base/test/thread_test_helper.cc
+++ b/base/test/thread_test_helper.cc
@@ -4,6 +4,8 @@
 
 #include "base/test/thread_test_helper.h"
 
+#include <utility>
+
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/threading/thread_restrictions.h"
@@ -13,9 +15,8 @@ namespace base {
 ThreadTestHelper::ThreadTestHelper(
     scoped_refptr<SingleThreadTaskRunner> target_thread)
     : test_result_(false),
-      target_thread_(target_thread.Pass()),
-      done_event_(false, false) {
-}
+      target_thread_(std::move(target_thread)),
+      done_event_(false, false) {}
 
 bool ThreadTestHelper::Run() {
   if (!target_thread_->PostTask(