Fix black screen during Quick switch

When quick switch a delayed task, before onTaskAppeared called,
if the user holds gesture on nav bar, TRANSIT_WALLPAPER_OPEN from closing
app happens will cancel recents animation when
WC#applyAnimationUnchecked, and that will cause the black screen if the
delayed task not yet drawn and there is no recents task snapshot on top.

Since cancelling recents animation during quick switching doesn't make
sense, to fix that, we should check the animation task target if is
still controlled by recents animation, if so, we should not cancel it.

Also, make sure if the appeared task has already been in task target list,
(i.e. task A appreared, quick switch to task B, before task B appeared,
quick switch back to task A) if so, we don't need to callback task
appeared again.

Fix: 156670249
Test: manual as issue test steps.
Change-Id: I303403d63c91c08fabcb8c5b1b1aac42c4ec65db