add a "capturing" condition for ExternalCapture

OpenRA.Mods.Common/Traits/Cloak.cs

@@ -173,6 +173,8 @@ namespace OpenRA.Mods.Common.Traits
 			firstTick = false;
 		}
 
+		protected override void TraitDisabled(Actor self) { Uncloak(); }
+
 		public bool IsVisible(Actor self, Player viewer)
 		{
 			if (!Cloaked || self.Owner.IsAlliedWith(viewer))

OpenRA.Mods.Common/Traits/ExternalCaptures.cs

@@ -34,6 +34,10 @@ namespace OpenRA.Mods.Common.Traits
 
 		[VoiceReference] public readonly string Voice = "Action";
 
+		[GrantedConditionReference]
+		[Desc("Condition granted when capturing.")]
+		public readonly string CapturingCondition = null;
+
 		public readonly string CaptureCursor = "ability";
 		public readonly string CaptureBlockedCursor = "move-blocked";