Rotation lock fix for sensor{Landscape,Portrait} activities.

E.g. if an app is sensorLandscape and the device rotation is
locked to landscape, the activity should not be allowed to
flip to seascape even if the device is inverted.

If the rotation is locked 90° from the activity's
supported orientations, we must override the lock as before,
but we now suppress the sensor input (confining the activity
to one of its two orientations). This best preserves the
spirit of the rotation lock while still allowing the
activity to run in a supported configuration.

Bug: 3453407
Change-Id: I8ee255e0250ba7e4534f4622ac37b82d31cf9936