Until someone picks a camera, a settled move re-opens CCTV on the camera
nearest the view and keeps the opening pick provisional. setActiveCamera
ends that opening pick, but for a camera that is already active and
activated it returns UNCHANGED before clearing the flag. So pressing
NEAREST on the camera a move had just re-opened (or selecting it from the
list, or through setParams) left the pick provisional, and the landing of
NEAREST's own flight, or the next pan, switched to another camera.
Clear the provisional flag on the UNCHANGED path too. reopenNearestCamera
only activates a different camera, so it is unaffected, and the same-camera
re-select still skips the activation work.
