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)

this.setLeading(-y);
      this.moveText(x, y);
    }
    setTextMatrix(a, b, c, d, e, f) {
      this.current.textMatrix = [a, b, c, d, e, f];
      this.current.textMatrixScale = Math.hypot(a, b);
      this.current.x = this.current.lineX = 0;
      this.current.y = this.current.lineY = 0;
    }
    nextLine() {
      this.moveText(0, this.current.leading);
    }
    paintChar(character, x, y, patternTransform, resetLineWidthToOne) {
      const ctx = this.ctx;
      const current = this.current;
      const font = current.font;
      const textRenderingMode = current.textRenderingMode;
      const fontSize = current.fontSize / current.fontSizeScale;
      const fillStrokeMode =
        textRenderingMode & TextRenderingMode.FILL_STROKE_MASK;
      const isAddToPathSet = !!(
        textRenderingMode & TextRenderingMode.ADD_TO_PATH_FLAG
      );
      const patternFill = current.patternFill && !font.missingFile;
      let addToPath;
      if (font.disableFontFace || isAddToPathSet || patternFill) {
        addToPath = font.getPathGenerator(this.commonObjs, character);
      }