ui-sref should use $set instead of raw access to set href

[nikaspran]

This is the line in question:

element[0][attr] = newHref;

Should be rewritten to use $set:

attrs.$set(attr, newHref);

This allows other directives to see the new href value and possibly manipulate it (the current approach means it happens outside of angular and it has no idea anything changed).

[nateabele]

Sounds good to me. Feel free to submit a PR if you would like this to happen in the near future.