Fix #1435: em units in font-size

Font-based units in the font-size property refer to the font-size
of the parent, not itself.
Implement Document's 'body' attribute

Implement Document's 'body' attribute (getter and setter). Proper
implementation of setter requires Node::ReplaceChild(), which is
currently a stub and will be done on a later step.

This patch is for:
https://github.com/mozilla/servo/issues/1428
auto merge of #1431 : brunoabinader/servo/document-body, r=jdm

Implement Document's 'body' attribute (getter and setter). Proper
implementation of setter requires Node::ReplaceChild(), which is
currently a stub and will be done on a later step.

This patch is for:
https://github.com/mozilla/servo/issues/1428
Add a test for percentages in font-size
auto merge of #1436 : SimonSapin/servo/font-size-em, r=kmcallister

Font-based units in the font-size property refer to the font-size of the parent, not itself.
Pass a Namespace to Element::get_attribute.
Pass a Namespace to Element::get_attr.
auto merge of #1438 : Ms2ger/servo/cleanup-get_attribute, r=jdm

Passing these around as strings is an anti-pattern, IMO.
Introduce methods to simplify implementing reflecting attributes.
Build with make instead of rustpkg.
auto merge of #1441 : metajack/servo/unrustpkg, r=metajack,me
fix build error on android(libuv 3.0)
add android graphic surface layer using EGL extensions
teporarily rollback of rust(because of uv error, we can not enter into amain. io errors are happened)
modify way to call main on android
add rust-egl to submodule
Servo-Android App packaging works
update glut_windowing for language change
update submodules
update gfx font stuffs for android