twitter/bootstrap — pull request #6118 by godric7 (2012-12-04 01:18:40+00:00)
Title: scrollSpy - add parent scrollTop to offset calculation

Fix for Bootstrap issue #6013 "scrollSpy - offset calculation"
https://github.com/twitter/bootstrap/issues/6013

When using scrollspy on div inside a container.
- If the div is already scrolled, the offset calculated are incorrects, sometimes < 0.
Adding the parents scrollTop value solves the issue.

Demo:
- http://jsfiddle.net/qu97u/35/