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 (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) {