Fix a couple of (likely rare) crashers that can happen if a tab is closed right as it's about to display a JS modal dialog.
Fix a couple of (likely rare) crashers that can happen if a tab is closed right as it's about to display a JS modal dialog.

I don't know how these would be triggered in the field.  I ran into them through misuse of the current API (trying to pass in a NULL WebContents).

Review URL: http://codereview.chromium.org/62079

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@13203 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser