DrawElements tests not respecting robust buffer access for offsets?

This test might assume we return an error in some cases that we could return robust access specified values:

https://www.khronos.org/registry/webgl/sdk/tests/conformance/rendering/draw-elements-out-of-bounds.html?webglVersion=1&quiet=0&quick=1

In particular this line:

```
PASS getError was expected value: INVALID_OPERATION : after evaluating: gl.drawElements(gl.TRIANGLES, 10000, gl.UNSIGNED_BYTE, 10000)
```

Wouldn't it be correct also to return NO_ERROR here? There's a few other tests that also fail with a change to ANGLE to avoid returning an error in these cases.

Start with the linked WebGL conformance test, especially the drawElements call and expected getError result. Compare that expectation with robust buffer access behavior and the ANGLE change mentioned in the issue; done means resolving whether the test should also accept NO_ERROR and accounting for the other affected tests.

Written by the indexing model from the issue text.