Move ".crx"/".pem" constants and extension_filenames constants into extensions/common/constants.cc.

chrome/common/extensions/api/i18n/default_locale_handler.cc

Index: chrome/common/extensions/api/i18n/default_locale_handler.cc
diff --git a/chrome/common/extensions/api/i18n/default_locale_handler.cc b/chrome/common/extensions/api/i18n/default_locale_handler.cc
index 363128fc0f256050b340625177ebdcbaa26d4ae3..3cae5fe2ed2820e1dc6dc2d5582dc918b6dcda2c 100644
--- a/chrome/common/extensions/api/i18n/default_locale_handler.cc
+++ b/chrome/common/extensions/api/i18n/default_locale_handler.cc
@@ -41,7 +41,7 @@ bool DefaultLocaleHandler::Parse(Extension* extension, string16* error) {
   if (!extension->manifest()->GetString(keys::kDefaultLocale,
                                         &info->default_locale) ||
       !l10n_util::IsValidLocaleSyntax(info->default_locale)) {
-    *error = ASCIIToUTF16(extension_manifest_errors::kInvalidDefaultLocale);
+    *error = ASCIIToUTF16(errors::kInvalidDefaultLocale);
     return false;
   }
   extension->SetManifestData(keys::kDefaultLocale, info.release());
@@ -53,10 +53,10 @@ bool DefaultLocaleHandler::Validate(
     std::string* error,
     std::vector<InstallWarning>* warnings) const {
   // default_locale and _locales have to be both present or both missing.
-  const base::FilePath path = extension->path().Append(kLocaleFolder);
+  const base::FilePath path =
+      extension->path().Append(filenames::kLocaleFolder);
   bool path_exists = base::PathExists(path);
-  std::string default_locale =
-      extensions::LocaleInfo::GetDefaultLocale(extension);
+  std::string default_locale = LocaleInfo::GetDefaultLocale(extension);
 
   // If both default locale and _locales folder are empty, skip verification.
   if (default_locale.empty() && !path_exists)
@@ -85,7 +85,8 @@ bool DefaultLocaleHandler::Validate(
                                                   all_locales))
       continue;
 
-    base::FilePath messages_path = locale_path.Append(kMessagesFilename);
+    base::FilePath messages_path =
+        locale_path.Append(filenames::kMessagesFilename);
 
     if (!base::PathExists(messages_path)) {
       *error = base::StringPrintf(