I'm sorry if it's a duplicate, I found lots of issues with gradients but none of the open ones looks similar.
It's apparently the PDF code `/Matrix [440 0 0 -200 20 220]` (line 44 in both files) that causes the problem.

**Configuration:**
- Web browser and its version: Chrome 54
- Operating system and its version: Windows 10
- PDF.js version: 1.6.343

**Steps to reproduce the problem:**
Open attached files:
[radial.pdf](https://github.com/mozilla/pdf.js/files/610302/radial.pdf)
[linear.pdf](https://github.com/mozilla/pdf.js/files/610300/linear.pdf)

**What is the expected behavior?** (Adobe Reader 11)
![image](https://cloud.githubusercontent.com/assets/17966696/20583379/fa80d780-b1f1-11e6-85d2-62dd6970a08c.png)

**What went wrong?** (mozilla.github.io/pdf.js/web/viewer.html)
Gradients aren't correctly transformed
![image](https://cloud.githubusercontent.com/assets/17966696/20583361/cf5bb8a4-b1f1-11e6-9479-9cc606b41187.png)

const activeSMask = this.current.activeSMask;
      const drawnWidth = activeSMask.canvas.width;
      const drawnHeight = activeSMask.canvas.height;
      const cacheId = "smaskGroupAt" + this.groupLevel;
      const scratchCanvas = this.cachedCanvases.getCanvas(
        cacheId,
        drawnWidth,
        drawnHeight,
        true
      );
      const currentCtx = this.ctx;
      const currentTransform = currentCtx.mozCurrentTransform;
      this.ctx.save();
      const groupCtx = scratchCanvas.context;
      groupCtx.scale(1 / activeSMask.scaleX, 1 / activeSMask.scaleY);
      groupCtx.translate(-activeSMask.offsetX, -activeSMask.offsetY);
      groupCtx.transform.apply(groupCtx, currentTransform);
      activeSMask.startTransformInverse = groupCtx.mozCurrentTransformInverse;
      copyCtxState(currentCtx, groupCtx);
      this.ctx = groupCtx;
      this.setGState([
        ["BM", "source-over"],
        ["ca", 1],
        ["CA", 1],
      ]);
      this.groupStack.push(currentCtx);
      this.groupLevel++;
    }
    suspendSMaskGroup() {