Replace DCHECK in the FileSystemQuota test code with ASSERT_TRUE.
Replace DCHECK in the FileSystemQuota test code with ASSERT_TRUE.

BUG=none
TEST=FileSystemQuotaTest.*
TBR=phajdan

Review URL: http://codereview.chromium.org/3638002

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@62017 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser