Position layers using their absolute position

Layers are currently all children of the root layer, so instead of
using coordinates relative to the parent flow we should use coordinates
relative to the page.

Fixes #2061.
auto merge of #3617 : mrobinson/servo/layer-positioning, r=pcwalton

Layers are currently all children of the root layer, so instead of
using coordinates relative to the parent flow we should use coordinates
relative to the page.

Fixes #2061.
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
layout: Make `box-sizing` only affect explicitly-specified or percentage
sizes, not automatically computed ones.

Improves GitHub significantly.
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
fix debian install instructions
Remove support for {return,native,concrete}Type overrides in Bindings.conf.

We have no reason to support non-default type names, and this commit corrects
the computations for callbacks (which needed the override until now).
Add [foo=bar i] case-insensitive attribute selectors.
Rewrite the user-agent stysheet(s)

Based on https://html.spec.whatwg.org/multipage/rendering.html
rather than http://dev.w3.org/csswg/css2/grammar.html
Disable failing reftest (#3636)
auto merge of #3637 : mbrubeck/servo/disable-link-style-reftest, r=pcwalton