Make the gonk port work again
CEF updates for Linux / MiniServo-GTK.
auto merge of #4317 : glennw/servo/linux-cef-fixes, r=pcwalton
auto merge of #4316 : michaelwu/servo/fix-gonk, r=glennw

This makes the gonk port build/work again after the recent CEF port update.
layout: Implement `text-transform`.

The Unicode awareness of `text-transform` is implemented as well as
possible given the Rust standard library's Unicode support. In
particular, the notion of an alphabetic character is used instead of a
letter.

Gecko has a subclass of text run to handle text transforms, but I
implemented this in a simpler way.
auto merge of #4311 : pcwalton/servo/text-transform, r=SimonSapin

The Unicode awareness of `text-transform` is implemented as well as
possible given the Rust standard library's Unicode support. In
particular, the notion of an alphabetic character is used instead of a
letter.

Gecko has a subclass of text run to handle text transforms, but I
implemented this in a simpler way.

r? @SimonSapin