We should figure out a way to mitigate the interop issue between Blink (Level 1) and WebKit (Level 2).

Some possible plans:
a. Implement Level 2 spec
  * See objections in https://docs.google.com/document/d/1yPZEkHl_WOPjVeilZjE1XmlyjLCe-uS7THI0SboyrMM/edit?usp=sharing
b. Persuade WebKit to go back to Level 1
  * Could be doable but the discussion came too late and missed their shipping schedule
c. Make all IME operations cancelable
  * Supported by yosin@ https://lists.w3.org/Archives/Public/public-editing-tf/2017Feb/0023.html


--- More Info ---
Blink Level 1 tracking bug:  issue 585875 
Intent to Ship: https://groups.google.com/a/chromium.org/d/msg/blink-dev/W-Q1yWW-zas/ezkF3lw9CAAJ

Level 1 Spec: https://www.w3.org/TR/2017/WD-input-events-1-20170321/
Level 2 Spec: https://www.w3.org/TR/2017/WD-input-events-2-20170321/
Chrome's PR to Level 1: https://github.com/w3c/input-events/pull/50

Related meeting notes: https://lists.w3.org/Archives/Public/public-editing-tf/2017Feb/0054.html