Move ReadFileToString to the base namespace.

chrome/common/extensions/api/storage/storage_schema_manifest_handler.cc

Index: chrome/common/extensions/api/storage/storage_schema_manifest_handler.cc
diff --git a/chrome/common/extensions/api/storage/storage_schema_manifest_handler.cc b/chrome/common/extensions/api/storage/storage_schema_manifest_handler.cc
index 6e49241745e0fcfac0a20fd3c27eb249613dfbb4..28c85576ad37a81963f855f8c9b4b91bb051f422 100644
--- a/chrome/common/extensions/api/storage/storage_schema_manifest_handler.cc
+++ b/chrome/common/extensions/api/storage/storage_schema_manifest_handler.cc
@@ -52,7 +52,7 @@ scoped_ptr<policy::PolicySchema> StorageSchemaManifestHandler::GetSchema(
     return scoped_ptr<policy::PolicySchema>();
   }
   std::string content;
-  if (!file_util::ReadFileToString(file, &content)) {
+  if (!base::ReadFileToString(file, &content)) {
     *error = base::StringPrintf("Can't read %s", file.value().c_str());
     return scoped_ptr<policy::PolicySchema>();
   }