Histograms for Favicon database recovery code.

http://crrev.com/225144 generates a histogram - but I forgot the
annotations, so I can't see them!  Oh noes!  I need to see them!

Also, I'm really excited to see what's happening.

BUG=240396
NOTRY=true
R=isherman@chromium.org

Review URL: https://codereview.chromium.org/24881002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225616 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225616