Plumb up DRI version and change workarounds based on it

Switches bool direct_rendering to string direct_rendering_version. This
allows us to plumb up what version of DRI is being used, when we can
reliably detect it.

This is motivated by the observation that we can safely re-enable
partial swaps on Linux when chrome is using DRI3.

Bug: 941670
Change-Id: I0cd8c12e28a6d9e8019e153bf7ff64907c4c3345
Reviewed-by: Robert Kroeger <>
Reviewed-by: Ken Buchanan <>
Reviewed-by: Antoine Labour <>
Reviewed-by: St├ęphane Marchesin <>
Commit-Queue: Jonathan Backer <>
Cr-Commit-Position: refs/heads/master@{#642639}
37 files changed