Faster Listener Deletion

Whenever a component is unmounted, we delete all listeners that might have been attached. This sucks because most applications, Facebook included, do not use every listener. There's a lot of wasted computation, especially if many components are mounted and unmounted.

This changes `deleteAllListeners` to more delete listeners more efficiently.

src/event/CallbackRegistry.js

@@ -35,7 +35,7 @@ var CallbackRegistry = {
   /**
    * Stores `listener` at `listenerBank[registrationName][id]`. Is idempotent.
    *
-   * @param {string} id ID of the DOM node.
+   * @param {string} id ID of the DOM element.
    * @param {string} registrationName Name of listener (e.g. `onClick`).
    * @param {?function} listener The callback to store.
    */
@@ -46,7 +46,7 @@ var CallbackRegistry = {
   },
 
   /**
-   * @param {string} id ID of the DOM node.
+   * @param {string} id ID of the DOM element.
    * @param {string} registrationName Name of listener (e.g. `onClick`).
    * @return {?function} The stored callback.
    */
@@ -58,7 +58,7 @@ var CallbackRegistry = {
   /**
    * Deletes a listener from the registration bank.
    *
-   * @param {string} id ID of the DOM node.
+   * @param {string} id ID of the DOM element.
    * @param {string} registrationName Name of listener (e.g. `onClick`).
    */
   deleteListener: function(id, registrationName) {
@@ -68,6 +68,17 @@ var CallbackRegistry = {
     }
   },
 
+  /**
+   * Deletes all listeners for the DOM element with the supplied ID.
+   *
+   * @param {string} id ID of the DOM element.
+   */
+  deleteAllListeners: function(id) {
+    for (var registrationName in listenerBank) {
+      delete listenerBank[registrationName][id];
+    }
+  },
+
   /**
    * This is needed for tests only. Do not use!
    */

src/event/EventPluginHub.js

@@ -112,17 +112,7 @@ var EventPluginHub = {
 
   deleteListener: CallbackRegistry.deleteListener,
 
-  /**
-   * Deletes all listeners for the DOM element with the supplied ID.
-   *
-   * @param {string} domID ID of a DOM element.
-   */
-  deleteAllListeners: function(domID) {
-    var registrationNamesKeys = EventPluginRegistry.registrationNamesKeys;
-    for (var ii = 0; ii < registrationNamesKeys.length; ii++) {
-      CallbackRegistry.deleteListener(domID, registrationNamesKeys[ii]);
-    }
-  },
+  deleteAllListeners: CallbackRegistry.deleteAllListeners,
 
   /**
    * Allows registered plugins an opportunity to extract events from top-level