Simplify event dispatching

This simplifies event dispatching by removing the `return false` special
case for the SimpleEventPlugin which allow us to inline much more here
and the code becomes easier to follow.

src/renderers/dom/client/__tests__/ReactBrowserEventEmitter-test.js

@@ -264,7 +264,7 @@ describe('ReactBrowserEventEmitter', function() {
     expect(idCallOrder[0]).toBe(getID(CHILD));
   });
 
-  it('should stopPropagation if false is returned, but warn', function() {
+  it('should not stopPropagation if false is returned', function() {
     ReactBrowserEventEmitter.putListener(
       getID(CHILD),
       ON_CLICK_KEY,
@@ -282,14 +282,11 @@ describe('ReactBrowserEventEmitter', function() {
     );
     spyOn(console, 'error');
     ReactTestUtils.Simulate.click(CHILD);
-    expect(idCallOrder.length).toBe(1);
+    expect(idCallOrder.length).toBe(3);
     expect(idCallOrder[0]).toBe(getID(CHILD));
-    expect(console.error.calls.length).toEqual(1);
-    expect(console.error.calls[0].args[0]).toBe(
-      'Warning: Returning `false` from an event handler is deprecated and ' +
-      'will be ignored in a future release. Instead, manually call ' +
-      'e.stopPropagation() or e.preventDefault(), as appropriate.'
-    );
+    expect(idCallOrder[1]).toBe(getID(PARENT));
+    expect(idCallOrder[2]).toBe(getID(GRANDPARENT));
+    expect(console.error.calls.length).toEqual(0);
   });
 
   /**

src/renderers/dom/client/eventPlugins/SimpleEventPlugin.js

@@ -13,7 +13,6 @@
 
 var EventConstants = require('EventConstants');
 var EventListener = require('EventListener');
-var EventPluginUtils = require('EventPluginUtils');
 var EventPropagators = require('EventPropagators');
 var ReactMount = require('ReactMount');
 var SyntheticClipboardEvent = require('SyntheticClipboardEvent');
@@ -30,7 +29,6 @@ var emptyFunction = require('emptyFunction');
 var getEventCharCode = require('getEventCharCode');
 var invariant = require('invariant');
 var keyOf = require('keyOf');
-var warning = require('warning');
 
 var topLevelTypes = EventConstants.topLevelTypes;
 
@@ -452,30 +450,6 @@ var SimpleEventPlugin = {
 
   eventTypes: eventTypes,
 
-  /**
-   * Same as the default implementation, except cancels the event when return
-   * value is false. This behavior will be disabled in a future release.
-   *
-   * @param {object} event Event to be dispatched.
-   * @param {function} listener Application-level callback.
-   * @param {string} domID DOM ID to pass to the callback.
-   */
-  executeDispatch: function(event, listener, domID) {
-    var returnValue = EventPluginUtils.executeDispatch(event, listener, domID);
-
-    warning(
-      typeof returnValue !== 'boolean',
-      'Returning `false` from an event handler is deprecated and will be ' +
-      'ignored in a future release. Instead, manually call ' +
-      'e.stopPropagation() or e.preventDefault(), as appropriate.'
-    );
-
-    if (returnValue === false) {
-      event.stopPropagation();
-      event.preventDefault();
-    }
-  },
-
   /**
    * @param {string} topLevelType Record from `EventConstants`.
    * @param {DOMEventTarget} topLevelTarget The listening component root node.

src/renderers/shared/event/EventPluginHub.js

@@ -39,13 +39,7 @@ var eventQueue = null;
  */
 var executeDispatchesAndRelease = function(event) {
   if (event) {
-    var executeDispatch = EventPluginUtils.executeDispatch;
-    // Plugins can provide custom behavior when dispatching events.
-    var PluginModule = EventPluginRegistry.getPluginModuleForEvent(event);
-    if (PluginModule && PluginModule.executeDispatch) {
-      executeDispatch = PluginModule.executeDispatch;
-    }
-    EventPluginUtils.executeDispatchesInOrder(event, executeDispatch);
+    EventPluginUtils.executeDispatchesInOrder(event);
 
     if (!event.isPersistent()) {
       event.constructor.release(event);

src/renderers/shared/event/EventPluginUtils.js

@@ -78,11 +78,22 @@ if (__DEV__) {
 }
 
 /**
- * Invokes `cb(event, listener, id)`. Avoids using call if no scope is
- * provided. The `(listener,id)` pair effectively forms the "dispatch" but are
- * kept separate to conserve memory.
+ * Dispatch the event to the listener.
+ * @param {SyntheticEvent} event SyntheticEvent to handle
+ * @param {function} listener Application-level callback
+ * @param {string} domID DOM id to pass to the callback.
  */
-function forEachEventDispatch(event, cb) {
+function executeDispatch(event, listener, domID) {
+  var type = event.type || 'unknown-event';
+  event.currentTarget = injection.Mount.getNode(domID);
+  ReactErrorUtils.invokeGuardedCallback(type, listener, event, domID);
+  event.currentTarget = null;
+}
+
+/**
+ * Standard/simple iteration through an event's collected dispatches.
+ */
+function executeDispatchesInOrder(event) {
   var dispatchListeners = event._dispatchListeners;
   var dispatchIDs = event._dispatchIDs;
   if (__DEV__) {
@@ -94,33 +105,11 @@ function forEachEventDispatch(event, cb) {
         break;
       }
       // Listeners and IDs are two parallel arrays that are always in sync.
-      cb(event, dispatchListeners[i], dispatchIDs[i]);
+      executeDispatch(event, dispatchListeners[i], dispatchIDs[i]);
     }
   } else if (dispatchListeners) {
-    cb(event, dispatchListeners, dispatchIDs);
+    executeDispatch(event, dispatchListeners, dispatchIDs);
   }
-}
-
-/**
- * Default implementation of PluginModule.executeDispatch().
- * @param {SyntheticEvent} event SyntheticEvent to handle
- * @param {function} listener Application-level callback
- * @param {string} domID DOM id to pass to the callback.
- */
-function executeDispatch(event, listener, domID) {
-  event.currentTarget = injection.Mount.getNode(domID);
-  var type = event.type || 'unknown-event';
-  var returnValue =
-    ReactErrorUtils.invokeGuardedCallback(type, listener, event, domID);
-  event.currentTarget = null;
-  return returnValue;
-}
-
-/**
- * Standard/simple iteration through an event's collected dispatches.
- */
-function executeDispatchesInOrder(event, cb) {
-  forEachEventDispatch(event, cb);
   event._dispatchListeners = null;
   event._dispatchIDs = null;
 }
@@ -210,7 +199,6 @@ var EventPluginUtils = {
   isStartish: isStartish,
 
   executeDirectDispatch: executeDirectDispatch,
-  executeDispatch: executeDispatch,
   executeDispatchesInOrder: executeDispatchesInOrder,
   executeDispatchesInOrderStopAtTrue: executeDispatchesInOrderStopAtTrue,
   hasDispatches: hasDispatches,