All platforms don't support same locales at the same time. Make locale check ...

chrome/common/extensions/extension_l10n_util.h

Index: chrome/common/extensions/extension_l10n_util.h
===================================================================
--- chrome/common/extensions/extension_l10n_util.h	(revision 40922)
+++ chrome/common/extensions/extension_l10n_util.h	(working copy)
@@ -72,6 +72,10 @@
 void GetParentLocales(const std::string& current_locale,
                       std::vector<std::string>* parent_locales);
 
+// Extends list of Chrome locales to them and their parents, so we can do
+// proper fallback.
+void GetAllLocales(std::set<std::string>* all_locales);
+
 // Adds valid locales to the extension.
 // 1. Do nothing if _locales directory is missing (not an error).
 // 2. Get list of Chrome locales.
@@ -95,6 +99,15 @@
     const std::set<std::string>& valid_locales,
     std::string* error);
 
+// Returns bool if directory has "." in the name (for .svn) or if it doesn't
+// belong to Chrome locales.
+// |locales_path| is extension_id/_locales
+// |locale_path| is extension_id/_locales/xx
+// |all_locales| is a set of all valid Chrome locales.
+bool ShouldSkipValidation(const FilePath& locales_path,
+                          const FilePath& locale_path,
+                          const std::set<std::string>& all_locales);
+
 }  // namespace extension_l10n_util
 
 #endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_L10N_UTIL_H_