Optimize and inline more validation. Previously on each draw call we were checking both the instanced and non-instanced attributes for overflow. On on-instanced draw calls we don't need to do any special checks for instanced attributes. Also we can inline more into the headers. This improves draw call performance slightly. Bug: angleproject:2966 Change-Id: Idf5861d2d9daf9fffd5c84f6a1ea5b23ac8ab713 Reviewed-on: https://chromium-review.googlesource.com/c/1390357 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Markus Tavenrath <matavenrath@nvidia.com>