Make IsDisabled a method on Actor.

This allows us to cache the disabled traits, which simplifies life for some callers since we relieve them of having to cache it, as well as improving perf for all IsDisabled calls.

OpenRA.Mods.Common/Traits/Render/WithIdleOverlay.cs

@@ -61,7 +61,6 @@ namespace OpenRA.Mods.Common.Traits
 		{
 			var rs = self.Trait<RenderSprites>();
 			var body = self.Trait<IBodyOrientation>();
-			var disabled = self.TraitsImplementing<IDisable>();
 
 			buildComplete = !self.HasTrait<Building>(); // always render instantly for units
 			overlay = new Animation(self.World, rs.GetImage(self));
@@ -70,7 +69,7 @@ namespace OpenRA.Mods.Common.Traits
 				new AnimationWithOffset(overlay,
 					() => body.LocalToWorld(info.Offset.Rotate(body.QuantizeOrientation(self, self.Orientation))),
 					() => IsTraitDisabled || !buildComplete,
-					() => info.PauseOnLowPower && disabled.Any(d => d.Disabled),
+					() => info.PauseOnLowPower && self.IsDisabled(),
 					p => WithTurret.ZOffsetFromCenter(self, p, 1)),
 				info.Palette, info.IsPlayerPalette);
 		}