layout: Implement `z-index`.
auto merge of #3599 : pcwalton/servo/z-index, r=glennw

r? @glennw
layout: Mark the styles of elements with pseudos as unshareable.

Makes multiple `<br>` elements work, since those are implemented via
`before` pseudos.
auto merge of #3600 : pcwalton/servo/pseudo-unshareable, r=mbrubeck

Makes multiple `<br>` elements work, since those are implemented via
`before` pseudos.

r? @mbrubeck
Allow passing a method, request body, and headers to the pipeline in LoadUrlMsg
Remove unnecessary `deref()`s (fixes #3586)
auto merge of #3620 : ttaubert/servo/issue/3586-remove-derefs, r=Manishearth

r? @Manishearth
Incremental Style Recalc

This patch puts in the initial framework for incremental reflow. Nodes' styles
are no longer recalculated unless the node has changed.

I've been hacking on the general problem of incremental reflow for the past
couple weeks, and I've yet to get a full implementation that actually passes all
the reftests + wikipedia + cnn. Therefore, I'm going to try to land the different
parts of it one by one.

This patch only does incremental style recalc, without incremental flow
construction, inline-size bubbling, reflow, or display lists. Those will be coming
in that order as I finish them.

At least with this strategy, I can land a working version of incremental reflow,
even if not yet complete.

r? @pcwalton
removed restyledamage
auto merge of #3590 : cgaebel/servo/slow-incremental-reflow-rebase, r=pcwalton

This patch puts in the initial framework for incremental reflow. Nodes' styles
are no longer recalculated unless the node has changed.

I've been hacking on the general problem of incremental reflow for the past
couple weeks, and I've yet to get a full implementation that actually passes all
the reftests + wikipedia + cnn. Therefore, I'm going to try to land the different
parts of it one by one.

This patch only does incremental style recalc, without incremental flow
construction, inline-size bubbling, reflow, or display lists. Those will be coming
in that order as I finish them.

At least with this strategy, I can land a working version of incremental reflow,
even if not yet complete.

r? @pcwalton
auto merge of #3626 : Manishearth/servo/form-prep, r=jdm

Framework for form submission
Use Gecko's simpler Bloom filter instead of one based on hash
stretching.

This preserves the usage of the Bloom filter throughout style recalc,
but the implementation is rewritten. Provides a 15% improvement on
Guardians of the Galaxy.