Returning false when trying to set magnetic translations on IDLE.

This ensures that the caller can set the translation of a notification
without magnetic effects if the magnetic row manager is IDLE. This is an
invalid state for this call. Thus, we also log an error.

Test: MagneticRowManagerImplTest
Flag: com.android.systemui.magnetic_notification_swipes
Bug: 392752275
Change-Id: I008bab3aa39199c74f7d2efee9de0cac53c515cc