Enable throttling in SwapBuffers
Enable throttling in SwapBuffers

flush_with_flags, when available, allows the driver to throttle.
Using this suppress input lag issues that can be observed in heavy
rendering situations on non-intel cards.

Signed-off-by: Axel Davy <2b6ef604b998fb81662f85c329e4fc020eae8e5d@ens.fr>
Cc: 0834b06c69a25d9c1d572232288dd776b75e5554@lists.freedesktop.org

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