Core: Added the attacker to IDamageModifier' GetDamageModifier

OpenRA.Game/Traits/Health.cs

@@ -82,7 +82,7 @@ namespace OpenRA.Traits
 			
 			/* apply the damage modifiers, if we have any. */
             var modifier = (float)self.TraitsImplementing<IDamageModifier>().Concat(self.Owner.PlayerActor.TraitsImplementing<IDamageModifier>())
-				.Select(t => t.GetDamageModifier(warhead)).Product();
+				.Select(t => t.GetDamageModifier(attacker, warhead)).Product();
 
 			damage = (int)(damage * modifier);