The ultimate solution to this is probably to change the binding of stop-loading so that C-g can behave
more like it does in emacs.  As long as C-g is used for stop-loading though, I'm not sure that we would
want to have the key do something different inside of text boxes than it does outside of them.
Improvements to Conkeror's focus system would also bear on this, because currently, a website is able to
automatically focus a particular widget (often done for search boxes).  In such a case, if C-g did not
call stop-loading, the user would not have a way to stop the page load.