Remove redundant parameter of onDescendantOrientationChanged

The freezeDisplayToken is only non-null when the requestingContainer
is ActivityRecord and mayFreezeScreenLocked is true. The token also
always belongs to the activity so they are the same thing.

The parameter should be left after window hierarchy merge. Now the
check of freeze is centralized to DisplayContent#updateOrientation.

Bug: 163976519
Test: WmTests
Change-Id: I918fcdaae227d0c9bf4738735d4ce27a18200f1e