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
```
const next2Dict = new Dict(
      const next00Dict = new Dict(
      const xref = new XRefMock([
        { ref: textWidgetRef, data: textWidgetDict },
        { ref: xDictRef, data: xDict },
        { ref: dDictRef, data: dDict },
        { ref: next0Ref, data: next0Dict },
        { ref: next00Ref, data: next00Dict },
        { ref: next1Ref, data: next1Dict },
        { ref: next2Ref, data: next2Dict },
      ]
      const JS = Name.get("JavaScript"
      const additionalActionsDict = new Dict(
      const eDict = new Dict(
      eDict.set("JS", "hello()"
      eDict.set("S", JS
      additionalActionsDict.set("E", eDict
      // Test the cycle detection here.
      xDict.set("JS", "world()"
      xDict.set("S", JS
      xDict.set("Next", [next0Ref, next1Ref, next2Ref, xDictRef]
      next0Dict.set("JS", "olleh()"
      next0Dict.set("S", JS
      next0Dict.set("Next", next00Ref
      next00Dict.set("JS", "foo()"
      next00Dict.set("S", JS
      next00Dict.set("Next", next0Ref
      next1Dict.set("JS", "dlrow()"
      next1Dict.set("S", JS
      next1Dict.set("Next", xDictRef