Tests for the window's length attribute
Update pull request #693

1. Add tests to check the child browsing context by frame, object and embed elements
2. Rename files and etc

Signed-off-by: xiaojunwu <xiaojunx.a.wu@intel.com>
Update test2.html as review suggestions
Remvoe an unuseful assertion
Update according to review comments
Remove assertion for HTMLMediaElement.seeking in the seeking event
Update an assertion
Merge pull request #693 from xiaojunwu/submission/xiaojunwu/window-length

Tests for the window's length attribute
Added idlharness tests for the MSE spec.
Remove pass conditions from currentTime test names

This made it clear that the negative test was already covered.
Merge pull request #716 from foolip/currentTime-test-names

Remove pass conditions from currentTime test names
Update to latest upstream testharness.js.
Simplify and tighten the test for seeking to a negative time
Updated to latest upstream wptserve.
Updated to latest-latest upstream wptserve.
Test seeking to Number.MAX_VALUE
Use movie_5.* instead of movie_300.* wherever possible

movie_5.* is faster to load, so is preferable where possible. All of the
tests already also use audio_5.*, which are even smaller, so this ought
not to expose any new problems. None of the test descriptions seem to
indicate that a big or slow-loading resource is required.
Remove common/domtestcase.js (unused)
Remove pass condition from some media test names
Merge pull request #723 from foolip/rm-media-pass-conditions

Remove pass condition from some media test names