Use tasks' orientation in multi-window activities

Multi-window spec say bounds aren't affected by activity changing
their requested orientation after initial launch. Therefore we shouldn't
pass their requested orientation to them in those cases.

Bug: 145556374
Test: Activities that request different orientations won't get
configurations that don't match their bounds.
Test: ActivityRecordTests

Change-Id: I7fdec464805633b8595a0c18adf8bc54112c7f66