Atomic: During commit ignore anything related to PageFlip, unless requested
Atomic: During commit ignore anything related to PageFlip, unless requested

We might be doing Commits for test purposes or for Atomic modsets/Cursor
updates. In this case, we dont expect a page flip call back. However,
in CommitProperties we dont check if DRM_MODE_PAGE_FLIP_EVENT is
set and always generate page flip ids and register for page flip call
backs (in case Test flag is not set). Make sure we check for
DRM_MODE_PAGE_FLIP_EVENT before doing anything related to PageFlip.

BUG=370522, 529381

Review URL: https://codereview.chromium.org/1348053003

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#349513}

axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk