bling/vim-airline — pull request #375 by qstrahl (2013-12-09 20:09:34+00:00)
Title: Correct quickfix window detection pattern

I stole this code for my own personal used and ran into some cases where the pattern wasn't matching. I took a look at it and noticed a `\s+` where there ought to have been a `\s*` match. It fixed the issue for me, so I offer the fix back to the source.