Merge pull request #286 from greggman/update-context-lost-restored-test

Update Context-lost-restored test to require extensions to be restorable...
Updated video tests to be more correct.

The video-related WebGL conformance tests
(tex-image-and-sub-image-2d-with-video.html with variants, and
texture-npot-video.html) currently start the test upon receiving the
"playing" event. After receiving feedback from the Chrome on Android
team, and studying the HTMLVideoElement spec, it seems that this is
incorrect.
http://www.w3.org/html/wg/drafts/html/master/embedded-content-0.html#mediaevents
says for the "playing" event: "Even if this event fires, the element
might still not be potentially playing".

Watching for a "timeupdate" event where the video's currentTime is
past the start time seems to be a more reliable heuristic.

There are bugs in Safari, including current WebKit nightlies, with
dynamically created video elements, and video elements with
style="display:none". This patch improves the reliability with
dynamically created video elements, but causes reliable failures with
display:none elements (used by texture-npot-video.html). This test was
already previously failing in Safari, so I believe it is warranted to
update all versions of these video tests in the same way to generally
improve their reliability, and assume that this bug will be fixed in
Safari at some point in the future.

Tested all versions of these tests with Chrome, Firefox and Safari on
Mac OS. Chrome and Firefox pass the tests completely. The current
WebKit nightly now passes the 1.0.2 and top of tree
tex-image-and-sub-image-with-video.html tests, where it was failing
them before.
Addressed Gregg Tavares's review feedback: refactored new video callback logic into helper functions on WebGLTestUtils.
Revised based on Gregg Tavares's review feedback. Simplified to WebGLTestUtils.startPlayingAndWaitForVideo.
Merge pull request #287 from kenrussell/video-tests

Refactored video tests to be more correct.
Clarified WEBGL_lose_context error generation behavior
Minor verbiage change
Merge pull request #288 from toji/webgl_lose_context_error

Clarified WEBGL_lose_context error generation behavior
After discussion with the ECMAScript committee, the typed array editor's draft and ES6 draft specs have been changed so that the ArrayBufferView interface is no longer exposed, and the static method ArrayBuffer.isView is added for type tests. Updated the 1.0.2 and top of tree WebGL conformance tests to reflect these changes.
Merge pull request #290 from kenrussell/arraybufferisview

After discussion with the ECMAScript committee, the typed array editor's...
Updated ext-draw-buffers test to reflect new name, clarified naming in WEBGL_draw_buffers spec
Merge pull request #291 from toji/webgl_draw_buffers

Updated EXT_draw_buffers test to reflect new name
Backported Gregg's quickCheckAPI speedup to 1.0.1 suite
Backported Gregg's quickCheckAPI speedup to 1.0.2 suite
Merge pull request #292 from toji/quickcheck_speedup_port

Backport quickCheckAPI speedup to 1.0.1 and 1.0.2 suites
Update context-lost-restored test to check that
extensions are lost and not restorable. New extensions
must be enable after context restored