Finish the veil fade in if a move occurs.

Separates the veil and icon fade in into two separate animations and
finishes the former if the veil is resized while the aniamtion is running. This gives the appearance of fading in while preventing the adjusted bounds of a task from showing as empty space behind the transparent veil.

Bug: 296920474
Test: Manual
Change-Id: I0954a2f2e4d24a4b1d0c21747e2f5f0f12072ba8