**Link to PDF file (or attach file here):**
[tocheckFile.pdf](https://github.com/mozilla/pdf.js/files/240714/tocheckFile.pdf)

**Configuration:**
- Web browser and its version: FF45.0.2, Chrome Version 50.0.2661.86 (64-bit) 
- Operating system and its version: Mac OSX El Capitan

**\- PDF.js version:**
PDFJS.version = '1.1.215';
PDFJS.build = 'c9a7498';

**Steps to reproduce the problem:**
1. Use the lib to generate a PDF preview.

**What is the expected behavior? (add screenshot)**
PDF preview should have rendered completely. (frog head should be complete)

**What went wrong? (add screenshot)**
<img width="952" alt="imagesnotrenderinginpreview" src="https://cloud.githubusercontent.com/assets/10231850/14889265/cecb2d64-0d66-11e6-98e1-da2d39728552.png">

See attached screenshot in regards to the pdf file

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

0,
      width,
      height
    );
    fillCtx.globalCompositeOperation = "source-in";
    const inverse = Util.transform(fillCtx.mozCurrentTransformInverse, [
      1,
      0,
      0,
      1,
      -offsetX,
      -offsetY,
    ]);
    fillCtx.fillStyle = isPatternFill
      ? fillColor.getPattern(ctx, this, inverse, false)
      : fillColor;
    fillCtx.fillRect(0, 0, width, height);
    
    return {
      canvas: fillCanvas.canvas,
      offsetX: Math.round(offsetX),
      offsetY: Math.round(offsetY),
    };
  }
  
  setLineWidth(width) {
    this.current.lineWidth = width;
    this.ctx.lineWidth = width;
  }
  setLineCap(style) {