servo/servo — pull request #3890 by pcwalton (2014-11-05 08:57:26+00:00)
Title: gfx: Micro-optimize `DList` and `StackingContext` a bit.

I'm sad to say that this improved performance significantly. A lot of
this win is due to the Rust compiler not being smart about not zeroing
objects out if it doesn't need to.

r? @glennw