Track if uniform data has been updated to avoid extra Map calls. Compare all uniform data to the values currently stored in the uniform and only mark the uniform as dirty if the data is new. This saves lots of buffer map calls when the same data is set on a uniform many times. BUG=260069 Change-Id: Ic4df8a276a81b074211712ff50e5cc4d0d9bb612 Reviewed-on: https://chromium-review.googlesource.com/199346 Reviewed-by: Nicolas Capens <nicolascapens@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>