tree cdc6b1ad68b19c54d5f7c75f26a1f12fb73338d9
parent 536bc936d39b2d8fa000581665394eace54965bd
author Louis Chang <louischang@google.com> 1606812637 +0800
committer Louis Chang <louischang@google.com> 1606812637 +0800

Rename Stack to Task related terms (3/n)

Update most of methods and members with Stack terms in below files
- ActivityTaskManagerService
- RootWindowContainer
- ActivityTaskSupervisor
- DisplayContent
- TaskDisplayArea

No logical changes.

Bug: 157876447
Test: presubmit
Change-Id: I333c29916fa34fbccf9a7e172b79689b422259a3