There are applications that disable validation using
EGL_CONTEXT_OPENGL_NO_ERROR_KHR extension. In such usecases
the GetQueryObjectParameter() method needs to account for the
possibility that the query object has not yet been created.

Bug: angleproject:5704
Tests: angle_end2end_tests --gtest_filter=QueryObjectTest*
Change-Id: Ib9e1cb32a6d64f2772124178223cf07cbb84691b
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2729298Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Commit-Queue: Mohan Maiya <m.maiya@samsung.com>