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)

if (!this.contentVisible) {
        return;
      }
      const width = imgData.width;
      const height = imgData.height;
      const ctx = this.ctx;
      this.save();
      
      ctx.scale(1 / width, -1 / height);
      const currentTransform = ctx.mozCurrentTransformInverse;
      let widthScale = Math.max(
        Math.hypot(currentTransform[0], currentTransform[1]),
        1
      );
      let heightScale = Math.max(
        Math.hypot(currentTransform[2], currentTransform[3]),
        1
      );
      let imgToPaint, tmpCanvas, tmpCtx;
      
      if (
        (typeof HTMLElement === "function" && imgData instanceof HTMLElement) ||
        !imgData.data
      ) {
        imgToPaint = imgData;
      } else {
        tmpCanvas = this.cachedCanvases.getCanvas("inlineImage", width, height);