Clarify costs in onTransactionReady

- Only print full info of Task for dumpsys, because shouldBeVisible
  is a bit heavy. Though it relates to the default enabled debug log
  for shell transition, that still reduces some noise of the overhead
  and uninterested long log.
- Add a trace of createTaskSnapshot which is usually the major
  cost of onTransactionReady.
- Simplify a bit for scheduleAnimation:
 - The initial order of RWC was changed to after WindowAnimator.
   So it is non-null.
 - WC#scheduleAnimation has never been overridden for a long time.
   So just call the implementation directly instead of traversing
   to top parent.

Bug: 235323163
Test: CtsWindowManagerDeviceTestCases

Change-Id: Idd026e08efa1714b9bc52d5aa203b955e2bcce87