PLT-3077 Add group messaging (#5489)

* Implement server changes for group messaging

* Majority of client-side implementation

* Some server updates

* Added new React multiselect component

* Fix style issues

* Add custom renderer for options

* Fix model test

* Update ENTER functionality for multiselect control

* Remove buttons from multiselect UI control

* Updating group messaging UI (#5524)

* Move filter controls up a component level

* Scroll with arrow keys

* Updating mobile layout for multiselect (#5534)

* Fix race condition when backspacing quickly

* Hidden or new GMs show up for regular messages

* Add overriding of number remaining text

* Add UI filtering for team if config setting set

* Add icon to channel switcher and class prop to status icon

* Minor updates per feedback

* Improving group messaging UI (#5563)

* UX changes per feedback

* Update email for group messages

* UI fixes for group messaging (#5587)

* Fix missing localization string

* Add maximum users message when adding members to GM

* Fix input clearing on Android

* Updating group messaging UI (#5603)

* Updating UI for group messaging (#5604)

webapp/stores/modal_store.jsx

@@ -38,6 +38,7 @@ class ModalStoreClass extends EventEmitter {
         case ActionTypes.TOGGLE_GET_POST_LINK_MODAL:
         case ActionTypes.TOGGLE_GET_TEAM_INVITE_LINK_MODAL:
         case ActionTypes.TOGGLE_GET_PUBLIC_LINK_MODAL:
+        case ActionTypes.TOGGLE_DM_MODAL:
             this.emit(type, value, args);
             break;
         }

webapp/stores/notification_store.jsx

@@ -8,6 +8,7 @@ import UserStore from './user_store.jsx';
 import ChannelStore from './channel_store.jsx';
 import * as UserAgent from 'utils/user_agent.jsx';
 import * as Utils from 'utils/utils.jsx';
+import {buildGroupChannelName} from 'utils/channel_utils.jsx';
 import * as PostUtils from 'utils/post_utils.jsx';
 const ActionTypes = Constants.ActionTypes;
 
@@ -74,6 +75,8 @@ class NotificationStoreClass extends EventEmitter {
                 };
             } else if (channel.type === Constants.DM_CHANNEL) {
                 title = Utils.localizeMessage('notification.dm', 'Direct Message');
+            } else if (channel.type === Constants.GM_CHANNEL) {
+                title = buildGroupChannelName(channel.id);
             } else {
                 title = channel.display_name;
             }

webapp/stores/user_store.jsx

@@ -414,13 +414,18 @@ class UserStoreClass extends EventEmitter {
         userIds.splice(index, 1);
     }
 
-    getProfileListInChannel(channelId = ChannelStore.getCurrentId()) {
+    getProfileListInChannel(channelId = ChannelStore.getCurrentId(), skipCurrent = false) {
         const userIds = this.profiles_in_channel[channelId] || [];
+        const currentId = this.getCurrentId();
         const profiles = [];
 
         for (let i = 0; i < userIds.length; i++) {
             const profile = this.getProfile(userIds[i]);
             if (profile) {
+                if (skipCurrent && profile.id === currentId) {
+                    continue;
+                }
+
                 profiles.push(profile);
             }
         }