[Mac] Close file select dialogs when windows go away.
[Mac] Close file select dialogs when windows go away.

BUG=53361
TEST=Testcase in bug.
Review URL: http://codereview.chromium.org/3216004

git-svn-id: http://src.chromium.org/svn/trunk/src@57785 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 54672cd537c5946d769c45b695befa54e7ee5b8a
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser