implement more optimized EventHandle.off (#7137)

src/core/event-handle.js

@@ -39,7 +39,7 @@ class EventHandle {
 
     /**
      * @type {string}
-     * @private
+     * @ignore
      */
     name;
 
@@ -88,7 +88,7 @@ class EventHandle {
      */
     off() {
         if (this._removed) return;
-        this.handler.off(this.name, this.callback, this.scope);
+        this.handler.offByHandle(this);
     }
 
     on(name, callback, scope = this) {

src/core/event-handler.js

@@ -221,6 +221,40 @@ class EventHandler {
         return this;
     }
 
+    /**
+     * Detach an event handler from an event using EventHandle instance. More optimal remove
+     * as it does not have to scan callbacks array.
+     *
+     * @param {EventHandle} handle - Handle of event.
+     * @ignore
+     */
+    offByHandle(handle) {
+        const name = handle.name;
+        handle.removed = true;
+
+        // if we are removing a callback from the list that is executing right now
+        // ensure we preserve initial list before modifications
+        if (this._callbackActive.has(name) && this._callbackActive.get(name) === this._callbacks.get(name)) {
+            this._callbackActive.set(name, this._callbackActive.get(name).slice());
+        }
+
+        const callbacks = this._callbacks.get(name);
+        if (!callbacks) {
+            return this;
+        }
+
+        const ind = callbacks.indexOf(handle);
+        if (ind !== -1) {
+            callbacks.splice(ind, 1);
+
+            if (callbacks.length === 0) {
+                this._callbacks.delete(name);
+            }
+        }
+
+        return this;
+    }
+
     /**
      * Fire an event, all additional arguments are passed on to the event listener.
      *