While using pdfjs in frameworks with SSR like Next.js or Gatsby there is an error while build phase
```ReferenceError: window is not defined```

The error occurs at line 563 in `ui_utils.js`

Looks like all changes needs is:
```diff
const animationStarted = new Promise(function (resolve) {
  if (
    typeof PDFJSDev !== "undefined" &&
-   PDFJSDev.test("LIB && TESTING") &&
+   PDFJSDev.test("LIB && TESTING") ||
    typeof window === "undefined"
  ) {
    // Prevent "ReferenceError: window is not defined" errors when running the
    // unit-tests in Node.js/Travis.
    setTimeout(resolve, 20);
    return;
  }
  window.requestAnimationFrame(resolve);
});
```

There is an issue in react-pdf: https://github.com/wojtekmaj/react-pdf/issues/657
firstVisibleElementInd = backtrackBeforeAllVisibleElements(
      firstVisibleElementInd,
      views,
      top
    );
  }
  
  
  
  
  
  
  
  
  let lastEdge = horizontal ? right : -1;
  for (let i = firstVisibleElementInd; i < numViews; i++) {
    const view = views[i],
      element = view.div;
    const currentWidth = element.offsetLeft + element.clientLeft;
    const currentHeight = element.offsetTop + element.clientTop;
    const viewWidth = element.clientWidth,
      viewHeight = element.clientHeight;
    const viewRight = currentWidth + viewWidth;
    const viewBottom = currentHeight + viewHeight;
    if (lastEdge === -1) {