Handle destruction of select file dialog listener object in tab contents destructor.
Handle destruction of select file dialog listener object in tab contents destructor.

BUG=45400
TEST=None

Review URL: http://codereview.chromium.org/2856082

git-svn-id: http://src.chromium.org/svn/trunk/src@54763 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 2f7b43c02a42a84b2b2a6c05c638d20c64fca2b9
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