Apply consistent widget method names. Semantic change: Widgets that want to tick when !Visible must override TickOuter() instead of Tick().

OpenRA.Game/Widgets/PerfGraphWidget.cs

@@ -18,7 +18,7 @@ namespace OpenRA.Widgets
 	{
 		public PerfGraphWidget() : base() { }
 
-		public override void DrawInner()
+		public override void Draw()
 		{
 			var rect = RenderBounds;
 			float2 origin = Game.viewport.Location + new float2(rect.Right, rect.Bottom);