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

base/files/important_file_writer.cc

Index: base/files/important_file_writer.cc
diff --git a/base/files/important_file_writer.cc b/base/files/important_file_writer.cc
index 1529107bdf36c114c90ed60a67534d75b0a4dbb0..4af7137b6c95c582cce9e2b43c78843ac8f8a672 100644
--- a/base/files/important_file_writer.cc
+++ b/base/files/important_file_writer.cc
@@ -5,8 +5,8 @@
 #include "base/files/important_file_writer.h"
 
 #include <stdio.h>
-
 #include <string>
+#include <utility>
 
 #include "base/bind.h"
 #include "base/critical_closure.h"
@@ -191,7 +191,7 @@ void ImportantFileWriter::DoScheduledWrite() {
   DCHECK(serializer_);
   scoped_ptr<std::string> data(new std::string);
   if (serializer_->SerializeData(data.get())) {
-    WriteNow(data.Pass());
+    WriteNow(std::move(data));
   } else {
     DLOG(WARNING) << "failed to serialize data to be saved in "
                   << path_.value();