Comment 17 for bug 1174909

bisected down to this commit http://cgit.freedesktop.org/cairo/diff/?id=bdf83008f4b2c723fd8e65e2a92bc47a2e7bc442

commit bdf83008f4b2c723fd8e65e2a92bc47a2e7bc442
Author: Chris Wilson <email address hidden>
Date: Sat Aug 25 08:39:30 2012 +0100

    compositor: Skip invisible strokes

    If the pen is reduced to a single point, it is effectively invisible
    when rasterised, so skip the stroke composition.

    Signed-off-by: Chris Wilson <email address hidden>

commit fc38d7375d4f0342ece91596d71f0ce56aa2c975