Deprecate IActionBlocker in favour of cancellable events (#4193)

* Deprecate IActionBlocker in favour of cancellable events

* Bring back old speech/emoting component restrictions

* Rename action blocker listener methods

* Use Entity System public methods instead of extension methods

Co-authored-by: Vera Aguilera Puerto <gradientvera@outlook.com>

Content.Shared/Emoting/EmoteSystem.cs

@@ -0,0 +1,22 @@
+using Robust.Shared.GameObjects;
+
+namespace Content.Shared.Emoting
+{
+    public class EmoteSystem : EntitySystem
+    {
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            SubscribeLocalEvent<EmoteAttemptEvent>(OnEmoteAttempt);
+        }
+
+        private void OnEmoteAttempt(EmoteAttemptEvent ev)
+        {
+            if (!ev.Entity.HasComponent<SharedEmotingComponent>())
+            {
+                ev.Cancel();
+            }
+        }
+    }
+}