Use of base::StringPairs appropriately in nacl.

components/nacl/renderer/json_manifest.h

Index: components/nacl/renderer/json_manifest.h
diff --git a/components/nacl/renderer/json_manifest.h b/components/nacl/renderer/json_manifest.h
index 4117966ba6606db917b8070e5f0c4c2e8b68be93..7e3c84113f53d8665a714e71d03ad677301d6706 100644
--- a/components/nacl/renderer/json_manifest.h
+++ b/components/nacl/renderer/json_manifest.h
@@ -9,6 +9,7 @@
 #include <string>
 #include <utility>
 
+#include "base/strings/string_split.h"
 #include "components/nacl/renderer/ppb_nacl_private.h"
 #include "ppapi/c/pp_array_output.h"
 #include "third_party/jsoncpp/source/include/json/value.h"
@@ -42,8 +43,7 @@ class JsonManifest {
 
   // Gets all the keys and their URLs in the "files" section that are
   // prefetchable.
-  void GetPrefetchableFiles(
-      std::vector<std::pair<std::string, std::string> >* out_files) const;
+  void GetPrefetchableFiles(base::StringPairs* out_files) const;
 
   // Resolves a key from the "files" section to a fully resolved URL,
   // i.e., relative URL values are fully expanded relative to the