Configuration:
- PDF.js version: 2.0.550

Steps to reproduce the problem:
1. Render document in SVG mode `renderMode="svg"`

What is the expected behavior? (add screenshot)
Rendering annotations same way as they rendered on canvas

What went wrong? (add screenshot)
```
Warning: Unimplemented operator beginAnnotations
Warning: Unimplemented operator endAnnotations
```
if (font.disableFontFace || patternFill) {
        ctx.save();
        ctx.translate(x, y);
        ctx.beginPath();
        addToPath(ctx, fontSize);
        if (patternTransform) {
          ctx.setTransform.apply(ctx, patternTransform);
        }
        if (
          fillStrokeMode === TextRenderingMode.FILL ||
          fillStrokeMode === TextRenderingMode.FILL_STROKE
        ) {
          ctx.fill();
        }
        if (
          fillStrokeMode === TextRenderingMode.STROKE ||
          fillStrokeMode === TextRenderingMode.FILL_STROKE
        ) {
          if (resetLineWidthToOne) {
            ctx.resetTransform();
            ctx.lineWidth = Math.round(this._combinedScaleFactor);
          }
          ctx.stroke();
        }
        ctx.restore();
      } else {
        if (
          fillStrokeMode === TextRenderingMode.FILL ||
          fillStrokeMode === TextRenderingMode.FILL_STROKE
        ) {