gles_ext_params: Implement CaptureGetTexLevelParameterivANGLE. As seen in CaptureGetTexParameteriv_params from capture_gles_2_0_params.cpp. Bug: angleproject:5645 Change-Id: Id687f73fd5d898e64e8a8bebe92ca50a0e096990 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2718044 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Cody Northrop <cnorthrop@google.com> Commit-Queue: Jamie Madill <jmadill@chromium.org>