anchor.diff:      if (htmlMember == null) return;
       if (!domMembers.isEmpty()) {
         htmlToDom[htmlMember.qualifiedName] = domMembers;
  -    }
  -    domMembers.forEach((m) =>
  +      //htmlToDom[htmlmembername] -> list of corresponding dom members
  +    }
  +    domMembers.forEach((m) => // add the html member name to the domToHtml
           domToHtml.putIfAbsent(m, () => new Set()).add(htmlMember));
     }
   
  
positive.code:   /**
     * Computes the `dart:dom_deprecated` to `dart:html` mapping, and
     * places it in [domToHtml], [htmlToDom], [domTypesToHtml], and
     * [htmlTypesToDom]. Before this is run, Frog should be initialized
     * (via [parseOptions] and [initializeWorld]) and
     * [HtmlDiff.initialize] should be called.
     */
  
negative.code:       final domTypes = htmlToDomTypes(htmlType);
        if (domTypes.isEmpty()) continue;
  
        htmlTypesToDom.putIfAbsent(htmlType.qualifiedName,// map of html->[its dom types]
            () => new Set()).addAll(domTypes);
        domTypes.forEach((t) => // map of dom type -> [the html name].
            domTypesToHtml.putIfAbsent(t.qualifiedName,
              () => new Set()).add(htmlType));
  
        htmlType.declaredMembers.forEach(
            (_, m) => _addMemberDiff(m, domTypes)); // add those dom member types to each
            // of the html member (name/type) we're looking at
      }
    }
  
  