Rename counter classes to avoid confusing.

osu.Game/Graphics/UserInterface/KeyCounterCollection.cs

@@ -0,0 +1,26 @@
+//Copyright (c) 2007-2016 ppy Pty Ltd <contact@ppy.sh>.
+//Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using OpenTK;
+using osu.Framework.Graphics.Containers;
+
+namespace osu.Game.Graphics.UserInterface
+{
+    public class KeyCounterCollection : FlowContainer
+    {
+        public KeyCounterCollection()
+        {
+            Direction = FlowDirection.HorizontalOnly;
+        }
+
+        public void AddKey(KeyCounter key)
+        {
+            key.ParentCounter = this;
+            base.Add(key);
+        }
+
+        public override bool Contains(Vector2 screenSpacePos) => true;
+
+        public bool IsCounting { get; set; }
+    }
+}