Make sure surface crop is up-to-date when moving to front

Before, when a TaskFragment is resized when moving to front, its surface
may still be croped for the old bounds. Now, we make sure the surface
crop is updated when moving to front.

Bug: 207070762
Test: manually verify with resizing display in background
Change-Id: I2103a1d8db855624310bc3becd9ed502fb082a7f