Minimize the API calls done by InputLayoutCache::applyVertexBuffers. Reduce the number of IASetInputLayout calls to 1 in all cases and set the fewest number of buffers at once. BUG=260069 Change-Id: I059337fc6601ecefd801ef37546935becaa0d355 Reviewed-on: https://chromium-review.googlesource.com/199345 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Shannon Woods <shannonwoods@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>