ref(chat): de-parameterize AbstractMessageContainer

react/features/chat/components/AbstractMessageContainer.js

  *
  * @extends PureComponent
  */
-export default class AbstractMessageContainer<P: Props> extends PureComponent<P> {
+export default class AbstractMessageContainer extends PureComponent<Props> {
     static defaultProps = {
         messages: []
     };

react/features/chat/components/native/MessageContainer.js

 /**
  * Implements a container to render all the chat messages in a conference.
  */
-export default class MessageContainer extends AbstractMessageContainer<Props> {
+export default class MessageContainer extends AbstractMessageContainer {
     /**
      * Instantiates a new instance of the component.
      *

react/features/chat/components/web/MessageContainer.js

  *
  * @extends AbstractMessageContainer
  */
-export default class MessageContainer extends AbstractMessageContainer<Props> {
+export default class MessageContainer extends AbstractMessageContainer {
     /**
      * Reference to the HTML element at the end of the list of displayed chat
      * messages. Used for scrolling to the end of the chat messages.