GitLab

Clear prefs that the server reports TYPE_NULL values for and log a warning if the type is off otherwise.

BUG=none
TEST=compiles and passes tests

Review URL: http://codereview.chromium.org/6288016

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@72786 0039d316-1c4b-4281-b951-d872f2087c98