Alex Goins authored Jun 16, 2016 and Adam Jackson committed Jun 28, 2016

Adds typedefs for (*RRStartFlippingPixmapTrackingProcPtr),
(*RREnableSharedPixmapFlippingProcPtr),
and (*RRDisableSharedPixmapFlippingProcPtr) in randrstr.h.

Adds typedefs for (*PresentSharedPixmapProcPtr),
(*SharedPixmapNotifyDamageProcPtr),
(*RequestSharedPixmapNotifyDamageProcPtr), and
(*StopFlippingPixmapTrackingProcPtr) in scrnintstr.h.

Adds RR(Enable/Disable)SharedPixmapFlipping, and
RRStartFlippingPixmapTracking to rrScrnPrivRec.

Adds StopFlippingPixmapTracking, PresentSharedPixmap,
SharedPixmapNotifyDamage, and RequestSharedPixmapNotifyDamage to ScreenRec.

rrScrnPrivRec used for functions that use RandR-private data types, and
ScreenRec used for the rest.

RREnableSharedPixmapFlipping will allow the sink driver to setup for
flipping between two shared pixmaps.

RRDisableSharedPixmapFlipping will allow the sink driver to do teardown
associated with flipping between two shared pixmaps.

(RRStart/Stop)FlippingPixmapTracking are merely the double-buffered
equivalents of (Start/Stop)PixmapTracking, allowing the source driver to do
whatever setup and teardown necessary for presenting on the two shared
pixmaps.

PresentSharedPixmap is a function exposed by the source driver for the X
server or sink driver to call to request a present on a given shared
pixmap.  This way, presents can be driven by the sink's vblank instead of a
timer or similar mechanism.

SharedPixmapNotifyDamage and RequestSharedPixmapNotifyDamage are OPTIONAL
(even for double-buffered PRIME) functions exposed by the sink driver and
the source driver, respectively. By calling
master->RequestSharedPixmapNotifyDamage(ppix), the sink driver can request
for the source driver to call slave->SharedPixmapNotifyDamage(ppix) in
response to damage on the master screen pixmap tracked by ppix.

v1: Initial commit
v2: Rename PresentTrackedFlippingPixmap to PresentSharedPixmap
    Add SharedPixmapNotifyDamage / RequestSharedPixmapNotifyDamage
v3: Add RRCrtcPtr as a parameter to StartFlippingPixmapTracking
    Move functions that use RandR-private data types to rrScrnPrivRec.
v4: Unchanged
v5: Add front and back parameters to RREnableSharedPixmapFlippingProcPtr
v6: Rebase onto ToT
v7: Unchanged

Reviewed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Alex Goins <agoins@nvidia.com>