Attach (recommended) or Link to PDF file here: https://www.recom-power.com/pdf/Powerline-AC-DC/RAC05-K.pdf

Configuration:
- Web browser and its version: Firefox 56.0 (64-bit)
- Operating system and its version: Windows 10 with OS Build 15063.632
- PDF.js version: ?
- Is an extension: Built-in

Steps to reproduce the problem:
1. Open Page

What is the expected behavior? To properly render the first page. 
![image](https://user-images.githubusercontent.com/1151969/31415345-b1504022-add7-11e7-855b-8030a308f7a2.png)

What went wrong? Renders poorly.
![image](https://user-images.githubusercontent.com/1151969/31415363-d8842096-add7-11e7-818d-728c1102891b.png)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension): ?

const length = arr.length;
  
  if (length === 1 && arr[0] instanceof Uint8Array) {
    return arr[0];
  }
  let resultLength = 0;
  for (let i = 0; i < length; i++) {
    resultLength += arrayByteLength(arr[i]);
  }
  let pos = 0;
  const data = new Uint8Array(resultLength);
  for (let i = 0; i < length; i++) {
    let item = arr[i];
    if (!(item instanceof Uint8Array)) {
      if (typeof item === "string") {
        item = stringToBytes(item);
      } else {
        item = new Uint8Array(item);
      }
    }
    const itemLength = item.byteLength;
    data.set(item, pos);
    pos += itemLength;
  }
  return data;
}
function string32(value) {