**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):

if (this.current.resumeSMaskCtx) {
      this.resumeSMaskGroup();
    }
    
    
    if (
      this.current.activeSMask !== null &&
      (this.stateStack.length === 0 ||
        this.stateStack[this.stateStack.length - 1].activeSMask !==
          this.current.activeSMask)
    ) {
      this.endSMaskGroup();
    }
    if (this.stateStack.length !== 0) {
      this.current = this.stateStack.pop();
      this.ctx.restore();
      
      this.pendingClip = null;
      this._cachedGetSinglePixelWidth = null;
    } else {
      
      this.current.activeSMask = null;
    }
  }
  transform(a, b, c, d, e, f) {