Move local participant join to base/participants

react/features/app/components/AbstractApp.js

 import Thunk from 'redux-thunk';
 
 import { i18next } from '../../base/i18n';
-import {
-    localParticipantJoined,
-    localParticipantLeft
-} from '../../base/participants';
+import { localParticipantLeft } from '../../base/participants';
 import { Fragment, RouteRegistry } from '../../base/react';
 import { MiddlewareRegistry, ReducerRegistry } from '../../base/redux';
 import { SoundCollection } from '../../base/sounds';
      */
     componentWillMount() {
         this._init.then(() => {
-            const { dispatch, getState } = this._getStore();
+            const { dispatch } = this._getStore();
 
             dispatch(appWillMount(this));
 
-            // FIXME I believe it makes more sense for a middleware to dispatch
-            // localParticipantJoined on APP_WILL_MOUNT because the order of
-            // actions is important, not the call site. Moreover, we've got
-            // localParticipant business logic in the React Component
-            // (i.e. UI) AbstractApp now.
-
-            const settings = getState()['features/base/settings'];
-            const localParticipant = {
-                avatarID: settings.avatarID,
-                avatarURL: settings.avatarURL,
-                email: settings.email,
-                name: settings.displayName
-            };
-
             // We set the initialized state here and not in the contructor to
             // make sure that {@code componentWillMount} gets invoked before
             // the app tries to render the actual app content.
                 appAsyncInitialized: true
             });
 
-            dispatch(localParticipantJoined(localParticipant));
-
             // If a URL was explicitly specified to this React Component,
             // then open it; otherwise, use a default.
             this._openURL(toURLString(this.props.url) || this._getDefaultURL());

react/features/base/participants/middleware.js

 
 import {
     localParticipantIdChanged,
+    localParticipantJoined,
     participantUpdated
 } from './actions';
 import {
     switch (action.type) {
     case APP_WILL_MOUNT:
         _registerSounds(store);
-        break;
+
+        return _localParticipantJoined(store, next, action);
     case APP_WILL_UNMOUNT:
         _unregisterSounds(store);
         break;
     return next(action);
 });
 
+/**
+ * Initializes the local participant and signals that it joined.
+ *
+ * @private
+ * @param {Store} store - The Redux store.
+ * @param {Dispatch} next - The redux dispatch function to dispatch the
+ * specified action to the specified store.
+ * @param {Action} action - The redux action which is being dispatched
+ * in the specified store.
+ * @private
+ * @returns {Object} The value returned by {@code next(action)}.
+ */
+function _localParticipantJoined({ getState, dispatch }, next, action) {
+    const result = next(action);
+    const settings = getState()['features/base/settings'];
+    const localParticipant = {
+        avatarID: settings.avatarID,
+        avatarURL: settings.avatarURL,
+        email: settings.email,
+        name: settings.displayName
+    };
+
+    dispatch(localParticipantJoined(localParticipant));
+
+    return result;
+}
+
 /**
  * Plays sounds when participants join/leave conference.
  *