Increase coverage % for oauth2client.appengine.

Reviewed in http://codereview.appspot.com/5795070/.
diff --git a/oauth2client/appengine.py b/oauth2client/appengine.py
index 1420279..b484c1e 100644
--- a/oauth2client/appengine.py
+++ b/oauth2client/appengine.py
@@ -448,7 +448,8 @@
 
     Args:
       filename: string, File name of client secrets.
-      scope: string, Space separated list of scopes.
+      scope: string or list of strings, scope(s) of the credentials being
+        requested.
       message: string, A friendly string to display to the user if the
         clientsecrets file is missing or invalid. The message may contain HTML and
         will be presented on the web interface for any method that uses the
@@ -479,7 +480,8 @@
 
   Args:
     filename: string, File name of client secrets.
-    scope: string, Space separated list of scopes.
+    scope: string or list of strings, scope(s) of the credentials being
+      requested.
     message: string, A friendly string to display to the user if the
       clientsecrets file is missing or invalid. The message may contain HTML and
       will be presented on the web interface for any method that uses the