GitLab

* Remove a DCHECK about an empty database name that should not be there.
* Properly update the cached copy of the database_description.
* unit tests for the above

BUG=91651
Review URL: http://codereview.chromium.org/7748025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@98466 0039d316-1c4b-4281-b951-d872f2087c98