Don't remove task from recents if closed by caption button.

When the user clicks X in non client decor of a freeform task, we
don't want it to be removed from recents. The task gets finished,
but it will remain in recents.

Bug: 24718309

Change-Id: I8f47e310903ee7f839ec92f5c8ff3a9f1e09118c
2 files changed