Letterbox apps in multi-window if resizeable only due to supportsPictureInPicture.

Test: atest WmTests:ActivityRecordTests
Fix: 204453314
Fix: 204784257
Change-Id: I664742b033ad49a77ae21b28c7ade4011d123c74
(cherry picked from commit d07c18877456800a6aabec25d6e5126606eae552)
Merged-In:I664742b033ad49a77ae21b28c7ade4011d123c74
2 files changed