message: fix currentTheme not set in Representation.createMulti
diff: @@ -226,7 +226,7 @@ namespace Representation {
  let version = 0;
  const updated = new Subject<number>();
  const currentState = stateBuilder.create();
  - const currentTheme = Theme.createEmpty();
  + let currentTheme = Theme.createEmpty();
  let currentParams: P;
  let currentProps: PD.Values<P>;
  @@ -314,6 +314,7 @@ namespace Representation {
  }
  },
  setTheme: (theme: Theme) => {
  + currentTheme = theme;
  for (let i = 0, il = reprList.length; i < il; ++i) {
  reprList[i].setTheme(theme);
  }
  