Fix onReachedMaxAppCacheSize callback

Bug: 5869022

When appcache reached max size, a callback is triggered. The
second parameter of this callback was returning the used Web SQL
quota, which is a rather different concept then AppCache. Fix this
to return max database size.

Change-Id: Iee11f40aa9635eaa22e237d4ddfb98792c977497
2 files changed