Dates in the blame view change when daylight savings changes.

1. Open up the blame view of a file.
2. Fake a TZ daylight savings change on the client by doing (or wait until it happens):

   var $content = jQuery("#content");
   var offset = Number($content.attr("data-timezone"));
   $content.attr("data-timezone", offset + 60);
   

3. (BUG) Re-render the blame view without reloading the page (steps below). The date will have changed by an hour.
   1. Click "Diff to Previous"
   2. Click "Source View"
   3. Click Blame.

Expected: The date should be rendered in the TZ offset that was in affect at the date and should remain constant irrespective of any daylight saving changes on the client or the server.