message: Prevent escape to cancel edit from also scrolling to bottom
diff: @@ -160,9 +160,11 @@ class EditMessageComposer extends React.Component<IEditMessageComposerProps, ISt
  switch (action) {
  case MessageComposerAction.Send:
  this.sendEdit();
  + event.stopPropagation();
  event.preventDefault();
  break;
  case MessageComposerAction.CancelEditing:
  + event.stopPropagation();
  this.cancelEdit();
  break;
  case MessageComposerAction.EditPrevMessage: {
  