Improved eventSender handling of non-consecutive touch ids.
After event_sender sees a sequence of touch-cancels or
touch-releases that makes the current touch ids
non-consecutive, it can create duplicate touch-ids for newly
added touch points. See the bug for details. This CL fixes
this problem.
Moreover, event_sender cleans its cache of released touches
but not the canceled ones in SendCurrentTouchEvent. This CL
takes care of this too.
BUG=529807
Review URL: https://codereview.chromium.org/
1317733006
Cr-Commit-Position: refs/heads/master@{#347990}