Link to PDF file (or attach file here):
[RP_25884_V2_UEL Semi Finals 2016-17_concepts.pdf](https://github.com/mozilla/pdf.js/files/994423/RP_25884_V2_UEL.Semi.Finals.2016-17_concepts.pdf)

Configuration:
- Web browser and its version: Chrome 58, Firefox 53
- Operating system and its version: MacOS 10.11.6
- PDF.js version:
- Is an extension: No

Steps to reproduce the problem:
1.  View the file the file


What is the expected behavior? (add screenshot)
<img width="560" alt="screen shot 2017-05-11 at 2 06 36 pm" src="https://cloud.githubusercontent.com/assets/2474027/25971992/189f4ebe-3653-11e7-8847-c9011984cb8d.png">

What went wrong? (add screenshot)
Textlayer exists here but font fails to render. No warning in the console from what I can see. Maybe related to the gradient?

<img width="637" alt="screen shot 2017-05-11 at 2 06 20 pm" src="https://cloud.githubusercontent.com/assets/2474027/25971997/1b518cc6-3653-11e7-96c0-9a03ffcb7d6e.png">

Thanks!
result[2] = orderedX[2];
    } else {
      return null;
    }
    
    if (
      (orderedY[0] === rect1[1] && orderedY[1] === rect2[1]) ||
      (orderedY[0] === rect2[1] && orderedY[1] === rect1[1])
    ) {
      
      result[1] = orderedY[1];
      result[3] = orderedY[2];
    } else {
      return null;
    }
    return result;
  }
}
const PDFStringTranslateTable = [
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  0x2c7, 0x2c6, 0x2d9, 0x2dd, 0x2db, 0x2da, 0x2dc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
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  0, 0, 0, 0, 0, 0, 0, 0, 0x2022, 0x2020, 0x2021, 0x2026, 0x2014, 0x2013, 0x192,
  0x2044, 0x2039, 0x203a, 0x2212, 0x2030, 0x201e, 0x201c, 0x201d, 0x2018,
  0x2019, 0x201a, 0x2122, 0xfb01, 0xfb02, 0x141, 0x152, 0x160, 0x178, 0x17d,
  0x131, 0x142, 0x153, 0x161, 0x17e, 0, 0x20ac,
];
function stringToPDFString(str) {