Use position in FindEnumStringIndex.

This is a shorter and probably slightly more efficient to write the loop.
Propagate the result of wptrunner.run_tests out of run.py.

This ensures that unexpected results cause 'make check-wpt' to fail.
Update test expectations for #2172.
Update the expectations for Document-createEvent.html.
auto merge of #2178 : Ms2ger/servo/enum-position, r=jdm

This is a shorter and probably slightly more efficient to write the loop.
auto merge of #2180 : Ms2ger/servo/wpt-result, r=jdm

This ensures that unexpected results cause 'make check-wpt' to fail.
Remove not-yet-implemented methods from CharacterData.

This speeds up a web-platform-tests run by about 45 seconds (of 11-12 minutes)
by avoiding three timeouts.
auto merge of #2181 : Ms2ger/servo/update-expectation, r=jdm
auto merge of #2184 : Ms2ger/servo/remove-nyi-characterdata, r=jdm

This speeds up a web-platform-tests run by about 45 seconds (of 11-12 minutes)
by avoiding three timeouts.
Track MANIFEST.json
auto merge of #2187 : Manishearth/servo/manifest, r=Ms2ger

Since we are keeping the results of previous tests locally (in metadata/), we should probably also track the generated MANIFEST file.
It won't get updated locally when the ini files are updated, which can lead to an outdated manifest.
Convert ~[] to std::vec::Vec in FontStyle and FontGroup
Convert ~[] to std::vec::Vec in main/css
Convert ~[] to std::vec::Vec in main/compositing