Add a comment explaining the ownership model between AppModalDialog and the NativeDialog.
Add a comment explaining the ownership model between AppModalDialog
and the NativeDialog.

Review URL: http://codereview.chromium.org/77034


git-svn-id: http://src.chromium.org/svn/trunk/src@13942 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 32f9bfd861c3232a6f9b84bec31859210e5707cd
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