GTK: Remove use of deprecated gtk_dialog_set_has_separator

From GTK 2.22 the separator is off by default.

BUG=79722
TEST=Compiles on GTK2.16 and newer than 2.22


Review URL: http://codereview.chromium.org/9087008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@116342 0039d316-1c4b-4281-b951-d872f2087c98
5 files changed