Set proper stack in WM when activity is moved to stack in AM

When an activity is moved to a stack using the
ActivityStack#moveActivityToStack API a new task is created to
hold the activity in the stack. However, when the new task is
created in the window manager side it uses the stack id of the
previous stack the activity was in. We now pass the stack to use
from activity manager to window manager.

Bug: 25987309
Bug: 25961636
Change-Id: Iecc71f6d9b3e70a8d88e134b42f7532ba5327bad