Move Extension::GetBasicInfo to a static helper.

chrome/common/extensions/extension_constants.h

Index: chrome/common/extensions/extension_constants.h
diff --git a/chrome/common/extensions/extension_constants.h b/chrome/common/extensions/extension_constants.h
index a545d0af0b1c7fa4e073ed452ba066cb770dcf32..6bea68edc7dc0a0d11bc11fce9fd3e21de2eb452 100644
--- a/chrome/common/extensions/extension_constants.h
+++ b/chrome/common/extensions/extension_constants.h
@@ -76,21 +76,6 @@ namespace extension_filenames {
   extern const char kModulesDir[];
 }
 
-// Keys in the dictionary returned by Extension::GetBasicInfo().
-namespace extension_info_keys {
-  extern const char kDescriptionKey[];
-  extern const char kEnabledKey[];
-  extern const char kHomepageUrlKey[];
-  extern const char kIdKey[];
-  extern const char kNameKey[];
-  extern const char kKioskEnabledKey[];
-  extern const char kOfflineEnabledKey[];
-  extern const char kOptionsUrlKey[];
-  extern const char kDetailsUrlKey[];
-  extern const char kVersionKey[];
-  extern const char kPackagedAppKey[];
-}
-
 namespace extension_misc {
   // Matches chrome.windows.WINDOW_ID_NONE.
   const int kUnknownWindowId = -1;