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 b42e895fa9049d8c2e49ead59176fd534aad074a..5e07b3a0288e27e1b7383630607ecd673bc4ff9e 100644
--- a/chrome/browser/extensions/extension_service.h
+++ b/chrome/browser/extensions/extension_service.h
@@ -146,7 +146,11 @@ 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