Add fallback for missing remote animation callbacks

- In some cases WM won't callback the remote animation callbacks (neither
  start nor cancel) and Launcher never finishes executing the pending
  command (preventing the subsequent commands from running).  For the time
  being, just cancel the current state to allow the commands to be
  processed.

Bug: 194011186
Test: Mash on overview and home buttons with a 3p launcher

Signed-off-by: Winson Chung <winsonc@google.com>
Change-Id: I1b1296fab316b979f441ebb474d1475e3fa68f95
Merged-In: I1b1296fab316b979f441ebb474d1475e3fa68f95