message: refactor: create promise lazily
  When the promise was being created right away it caused an issues with Zones that was breaking Angular tests at Google.
diff: let nextHandle = 1;
  -const RESOLVED = (() => Promise.resolve())();
  +// The promise needs to be created lazily otherwise it won't be patched by Zones
  +let resolved: Promise<any>;
  const activeHandles: { [key: number]: any } = {};
  /**
  @@ -22,7 +23,10 @@ export const Immediate = {
  setImmediate(cb: () => void): number {
  const handle = nextHandle++;
  activeHandles[handle] = true;
  - RESOLVED.then(() => findAndClearHandle(handle) && cb());
  + if (!resolved) {
  + resolved = Promise.resolve();
  + }
  + resolved.then(() => findAndClearHandle(handle) && cb());
  return handle;
  },
  