Separate the syncing of extension settings and app settings into separate data

chrome/browser/extensions/extension_service.h

Index: chrome/browser/extensions/extension_service.h
diff --git a/chrome/browser/extensions/extension_service.h b/chrome/browser/extensions/extension_service.h
index 7e5e9f6c2e8b64aac5d6c7368cfa71a60463059b..52cfa2f11dafc89917196f02df87c4a9f7ce8c92 100644
--- a/chrome/browser/extensions/extension_service.h
+++ b/chrome/browser/extensions/extension_service.h
@@ -145,7 +145,11 @@ class ExtensionService
 
   // The name of the directory inside the profile where per-extension settings
   // are stored.
-  static const char* kSettingsDirectoryName;
+  static const char* kExtensionSettingsDirectoryName;
+
+  // The name of the directory inside the profile where per-app settings
+  // are stored.
+  static const char* kAppSettingsDirectoryName;
 
   // Determine if a given extension download should be treated as if it came
   // from the gallery. Note that this is requires *both* that the download_url