ajaxorg/ace — pull request #2002 by nightwing (2014-06-11 22:01:47+00:00)
Title: [WIP] Support variable-width text 

rebased version of #1608

TODO:
- [ ] add option to keep old behavior
- [ ] fix handling of wrapped lines
- [ ] rtl support (use range.getBoundingClientRect for measurements)
- [ ] gracefully handle scrollbar size changes from delayed measurements of line height/length