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 (count < MIN_CHARS_IN_BLOCK) {
      return i - ((i - iFirstBeginText) % 5);
    }
    
    
    
    let iFirst = iFirstBeginText;
    if (
      iFirstBeginText >= 4 &&
      fnArray[iFirstBeginText - 4] === fnArray[iFirstSetFont] &&
      fnArray[iFirstBeginText - 3] === fnArray[iFirstSetTextMatrix] &&
      fnArray[iFirstBeginText - 2] === fnArray[iFirstShowText] &&
      fnArray[iFirstBeginText - 1] === fnArray[iFirstEndText] &&
      argsArray[iFirstBeginText - 4][0] === firstSetFontArg0 &&
      argsArray[iFirstBeginText - 4][1] === firstSetFontArg1
    ) {
      count++;
      iFirst -= 5;
    }
    
    let iEndText = iFirst + 4;
    for (let q = 1; q < count; q++) {
      fnArray.splice(iEndText, 3);
      argsArray.splice(iEndText, 3);
      iEndText += 2;
    }
    return iEndText + 1;
  }
);
class NullOptimizer {