changed testing method in cache tests to avoid garbage when cache content is not ok
changed testing method in cache tests to avoid garbage when cache content is not ok

git-svn-id: 2f0e1b834f829f9d45d4005679b0d62d953a4cdf@3093 4396de85-42e0-4213-a939-0f47b466bcdf

morhekil/symfony,morhekil/symfony,morhekil/symfony