Add a gonk port.
Don't include the root element when calling Element#getElementsByTagName

Fixes #4249
auto merge of #4304 : ema-fox/servo/bytag, r=Ms2ger

Fixes #4249
Rename base_url to final_url in ScriptTask::load.

This seems like a clearer name, as it's used for more than just as a base url.
Pass a borrowed Url to parse_html.

It does not need to take ownership, and I want to reuse final_url in the
caller.
Reuse the final_url in ScriptTask::load.

In both the javascript and non-javascript url cases, final_url is set to the
same url as is stored by the Page.
Issue #1820 - Improve the Blob implementation
auto merge of #4108 : shinglyu/servo/blob, r=jdm

Let's build this incrementally. I implemented a `Blob` that can hold a `DOMString`, and has `size` attribute and `slice(...)` method. I'll finish the rest in later PRs.
Convert C code to Rust
Eliminate use of allow(dead_code) in window.rs
auto merge of #4305 : Ms2ger/servo/script_task, r=jdm
Update rust-openssl to add static linking for android.
auto merge of #4296 : glennw/servo/update-openssl, r=mbrubeck
Remove use of rustuv/green in the gonk port.
auto merge of #4306 : michaelwu/servo/gonk-port-three, r=glennw

Trying again since critic didn't notice https://github.com/servo/servo/pull/4294 .
auto merge of #4308 : michaelwu/servo/remove-libgreen, r=glennw

As requested during the review of the gonk port.
Remove unused code in assign_block_size_block_base

This code is unreachable because an earlier `if base(kid).flags.is_float()`
check bails out of the loop before it can reach this block.
Make all of LineBreaker private
auto merge of #4309 : mbrubeck/servo/float-cleanup, r=pcwalton

r? @SimonSapin or @pcwalton
Remove PseudoDisplayItemClass

Now that content box queries are made against the flow tree, we can
remove PseudoDisplayItems from the display list.