Race condition in test texImage2DHTML.html?

[asajeffrey]

I'm seeing FAIL results in Servo in test https://github.com/KhronosGroup/WebGL/blob/master/conformance-suites/2.0.0/conformance/more/functions/texImage2DHTML.html which I think may be caused by a race condition in the test.

The FAIL is caused by the testTexImage2DNonSOP test running before the <img id="i2"> has loaded, causing the ctx.drawImage(img,0,0) to throw an InvalidState exception. This happens when the test runs before the img is initialized at https://github.com/KhronosGroup/WebGL/blob/master/conformance-suites/2.0.0/conformance/more/functions/texImage2DHTML.html#L117

This seems to be a race condition between the document.load event which initializes the img, and the test running.

[jdm]

Also the specification for HTMLImageElement.complete was recently changed to remove the ability for its reported status to change inside of an endless loop like is used by that test: whatwg/html#4934

[kdashg]

I filed #2945 for while (!img.complete).