Change Validation For Indexed Draw Without ELEMENT_ARRAY_BUFFER Changed WebGL Validation to return INVALID_OPERATION any time an indexed draw call is made without a bound ELEMENT_ARRAY_BUFFER. Spec was changed to no longer require count > 0 in order to cause error. Make same spec change to GL_ANGLE_client_arrays extension. BUG:angleproject:2639 Change-Id: I23963f357119d081890aa5387b2863e1d42b92a5 Reviewed-on: https://chromium-review.googlesource.com/1093984 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org>