Don't use a separate channel to communicate window size to the
constellation.

This will make sandboxing much easier since we won't need a
separate Unix pipe just for this.
Silence CSS errors in the user-agent stylesheet.

Alternatively, we could comment the parts of that stylesheet that we don’t
support yet. (But we’d have to remember to uncomment them when we do!)
auto merge of #1192 : SimonSapin/servo/silence-ua-stylesheet-errors, r=jdm

Alternatively, we could comment the parts of that stylesheet that we don’t support yet. (But we’d have to remember to uncomment them when we do!)
Simplify Window wrapping.
Stop calling wrap_object_shared in WrapNewBindingObject and WrapNativeParent. Fixes #1083.
Remove Reflectable::wrap_object_shared.
auto merge of #1193 : Ms2ger/servo/wrap_object_shared, r=jdm
Pass a Reflector to WrapNewBindingObject instead of a Reflectable, and rename it GetReflector.
Remove DerivedWrapper.
auto merge of #1194 : Ms2ger/servo/DerivedWrapper, r=jdm
file_loader: Handle file-not-found and other error conditions
Remove render() bypass for headless mode

render() isn't called in headless mode because the headless compositor never
sends a ReRenderMsg.

(This code was needed originally and that probably changed when CPU rendering
landed, but I'm not sure exactly why.)
Remove WrapNativeParent and nearby cleanup.
Remove Reflectable::GetParentObject.
auto merge of #1198 : Ms2ger/servo/GetParentObject, r=jdm
auto merge of #1182 : pcwalton/servo/no-size-channel, r=metajack

This will make sandboxing much easier since we won't need a
separate Unix pipe just for this.
auto merge of #1195 : kmcallister/servo/headless, r=metajack
Parse `min-width` and `max-width`
Implement max-width, min-width for BlockFlow.
auto merge of #1150 : ILyoan/servo/max_width, r=ILyoan,metajack

For #783, only for block flow.
I'll do the things for other flows as well.

r? @simonsapin, @metajack