Change PrivetLocalPrinterLister to list all printers

PrivetLocalPrinterLister will list all printers and indicate if they
support local printing. This CL is part of adding registion promos for
unregistered printers to the print preview.

BUG=326718

Review URL: https://codereview.chromium.org/106283004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239355 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239355