Can't rely on checking location.pathname -- inside unload,
it already contains the new path. Fortunately, checking is
unnecessary.
Fixes TypeError: Cannot call method 'split' of undefined.
On Chrome, this lets clicks with modifier keys anywhere
on the changeset entry work as expected. On other browsers,
modifier keys still only work on the link itself.
The default click handler only handle the, not the rest of the
entry, so retore the handler but add an e.preventDefault() call
to stop the second handler running.
The default click handler in index.js handles them fine, and as this
one was not calling preventDefault both were actually firing in some
browsers, causing the changeset to be loaded twice and two history
entries to be created.
The general history view shows changesets in the current view
and updates when you move the map. The view for an individual
user, nearby users, or friends zooms the map to the extent of
the results, and doesn't change when you move the map.
