message: Prevent an exception getting scroll node
  Don't try to findDOMNode before we're mounted as it makes react
  angry.
diff: @@ -50,6 +50,8 @@ module.exports = React.createClass({
  },
  componentWillMount: function() {
  + this.mounted = false;
  +
  var cli = MatrixClientPeg.get();
  cli.on("Room", this.onRoom);
  cli.on("deleteRoom", this.onDeleteRoom);
  @@ -69,9 +71,12 @@ module.exports = React.createClass({
  this.dispatcherRef = dis.register(this.onAction);
  // Initialise the stickyHeaders when the component is created
  this._updateStickyHeaders(true);
  +
  + this.mounted = true;
  },
  - componentDidUpdate: function() {
  + componentDidUpdate: function(prevp, nextp) {
  + console.log(prevp, nextp);
  // Reinitialise the stickyHeaders when the component is updated
  this._updateStickyHeaders(true);
  this._repositionIncomingCallBox(undefined, false);
  @@ -106,6 +111,8 @@ module.exports = React.createClass({
  },
  componentWillUnmount: function() {
  + this.mounted = false;
  +
  dis.unregister(this.dispatcherRef);
  if (MatrixClientPeg.get()) {
  MatrixClientPeg.get().removeListener("Room", this.onRoom);
  @@ -311,6 +318,7 @@ module.exports = React.createClass({
  },
  _getScrollNode: function() {
  + if (!this.mounted) return null;
  var panel = ReactDOM.findDOMNode(this);
  if (!panel) return null;
  @@ -337,6 +345,7 @@ module.exports = React.createClass({
  var incomingCallBox = document.getElementById("incomingCallBox");
  if (incomingCallBox && incomingCallBox.parentElement) {
  var scrollArea = this._getScrollNode();
  + if (!scrollArea) return;
  // Use the offset of the top of the scroll area from the window
  // as this is used to calculate the CSS fixed top position for the stickies
  var scrollAreaOffset = scrollArea.getBoundingClientRect().top + window.pageYOffset;
  @@ -360,6 +369,7 @@ module.exports = React.createClass({
  // properly through React
  _initAndPositionStickyHeaders: function(initialise, scrollToPosition) {
  var scrollArea = this._getScrollNode();
  + if (!scrollArea) return;
  // Use the offset of the top of the scroll area from the window
  // as this is used to calculate the CSS fixed top position for the stickies
  var scrollAreaOffset = scrollArea.getBoundingClientRect().top + window.pageYOffset;
  