Unified coordinates in WebMouseEvent & WebTouchPoint.

This is a refactor-only change. Moved WebTouchPoint & WebMouseEvent
coordinates to WebPointerProperties after renaming the WebTouchPoint
fields.

Bug: 508283
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_site_isolation
Change-Id: If670e3be3cd67d23a2f266a8d37d5eaba204ba18
Reviewed-on: https://chromium-review.googlesource.com/517888
Reviewed-by: David Tapuska <[email protected]>
Reviewed-by: Avi Drissman <[email protected]>
Reviewed-by: Sadrul Chowdhury <[email protected]>
Reviewed-by: Raymes Khoury <[email protected]>
Reviewed-by: Kentaro Hara <[email protected]>
Commit-Queue: Mustaq Ahmed <[email protected]>
Cr-Commit-Position: refs/heads/master@{#476271}
43 files changed