Merge "docs: Updates to Multi-Window/PiP APIs for Preview 2" into mnc-mr-docs am: bd7c1b4 am: 194c1e6
am: c9344c3

* commit 'c9344c3e17be681f94bed55c91d52112e7a23a92':
  docs: Updates to Multi-Window/PiP APIs for Preview 2

Change-Id: Ib00de3d02a9aefd8bbb702f6ca9153b408acec21