Merge pull request #6445 from jfsiebel/chat-old-messages-re-render

...tton-html5/imports/ui/components/chat/alert/component.jsx

...tton-html5/imports/ui/components/chat/alert/container.jsx

...imports/ui/components/chat/alert/push-alert/component.jsx

...l5/imports/ui/components/chat/chat-dropdown/component.jsx

bigbluebutton-html5/imports/ui/components/chat/component.jsx

bigbluebutton-html5/imports/ui/components/chat/container.jsx

...ml5/imports/ui/components/chat/message-form/component.jsx

...ents/chat/message-form/message-form-actions/component.jsx

...onents/chat/message-form/message-form-actions/styles.scss

...ponents/chat/message-list/message-list-item/component.jsx

...chat/message-list/message-list-item/message/component.jsx

bigbluebutton-html5/imports/ui/components/chat/service.js