In the following spots a "MouseUp" eventName is being used, which does look inconsistent considering that the "Mouse Down"/"Mouse Enter"/"Mouse Exit" eventNames all have a space in them.
Is this inconsistency actually expected, or is it a simple typo? If the former, then a comment explaining *why* would be appropriate; otherwise we should just fix this :-)

 - https://github.com/mozilla/pdf.js/blob/25b84ce84c95ba06d1ee57e578672048269c39c1/src/display/annotation_layer.js#L806

 - https://github.com/mozilla/pdf.js/blob/25b84ce84c95ba06d1ee57e578672048269c39c1/src/display/annotation_layer.js#L945

 - https://github.com/mozilla/pdf.js/blob/25b84ce84c95ba06d1ee57e578672048269c39c1/src/display/annotation_layer.js#L1034

 - https://github.com/mozilla/pdf.js/blob/25b84ce84c95ba06d1ee57e578672048269c39c1/src/display/annotation_layer.js#L1168

/cc @calixteman 
{ ref: pupRef, data: pupDict },
        { ref: replyRef, data: replyDict },
      ]);
      annotationDict.assignXref(xref);
      pupDict.assignXref(xref);
      replyDict.assignXref(xref);
      AnnotationFactory.create(
        xref,
        replyRef,
        pdfManagerMock,
        idFactoryMock
      ).then(({ data }) => {
        expect(data.inReplyTo).toEqual(annotationRef.toString());
        expect(data.replyType).toEqual("R");
        expect(data.title).toEqual("ReplyTitle");
        expect(data.contents).toEqual("ReplyText");
        expect(data.creationDate).toEqual("D:20180523");
        expect(data.modificationDate).toEqual("D:20190523");
        expect(data.color).toEqual(new Uint8ClampedArray([102, 102, 102]));
        expect(data.hasPopup).toEqual(false);
        done();
      }, done.fail);
    });
  });
  describe("TextAnnotation", function () {
    it("should not parse state model and state when not defined", function (done) {
      const annotationRef = Ref.get(819, 0);
      const annotationDict = new Dict();
      annotationDict.set("Type", Name.get("Annot"));
      annotationDict.set("Subtype", Name.get("Text"));