Link to PDF file (or attach file here):
[pages4.pdf](https://github.com/mozilla/pdf.js/files/1128300/pages4.pdf)

Configuration:
- Web browser and its version: Firefox 54
- Operating system and its version: Win 10
- PDF.js version: 1.8.522
- Is an extension: no

What is the expected behavior? (add screenshot)
![chrome1-1 1](https://user-images.githubusercontent.com/146436/27918380-2f74512a-6245-11e7-8525-d0038fa6c2e8.jpg)
![chrome1-2 1](https://user-images.githubusercontent.com/146436/27918425-54f8e47e-6245-11e7-9bff-127f79ad0511.jpg)


What went wrong? (add screenshot)
![screenshot from 2017-07-06 12-10-30](https://user-images.githubusercontent.com/146436/27918442-5d57624e-6245-11e7-9436-5ba31cc8bd1a.png)
![screenshot from 2017-07-06 12-10-44](https://user-images.githubusercontent.com/146436/27918454-63b486da-6245-11e7-9eb5-c03aa5c40943.png)



const paths = this.pendingTextPaths;
    const ctx = this.ctx;
    if (paths === undefined) {
      ctx.beginPath();
      return;
    }
    ctx.save();
    ctx.beginPath();
    for (let i = 0; i < paths.length; i++) {
      const path = paths[i];
      ctx.setTransform.apply(ctx, path.transform);
      ctx.translate(path.x, path.y);
      path.addToPath(ctx, path.fontSize);
    }
    ctx.restore();
    ctx.clip();
    ctx.beginPath();
    delete this.pendingTextPaths;
  }
  setCharSpacing(spacing) {
    this.current.charSpacing = spacing;
  }
  setWordSpacing(spacing) {
    this.current.wordSpacing = spacing;
  }
  setHScale(scale) {
    this.current.textHScale = scale / 100;
  }
  setLeading(leading) {