This property sets which PlayerControlObject to use based on what team has control over the ObjectSpawner. It is also used for setting up plane and landing craft spawn points on ships.
Note that a spawn can be defined for only one team, so that a control point spawns vehicles only when one side owns it. An example of this is at the Battle of the Bulge level, where the Allies spawn a tank at the windmill but the Axis spawn nothing. If the second argument is not present, then nothing spawns for that team.
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