anchor.diff:  
       var importUri = _getSourceUri(element, from: entryPoint);
       var spanPath = importUri != null ? importUri.toString() : assetId.path;
  -    return new SourceFile.text(spanPath, sources[assetId].contents);
  +    return new SourceFile.text(spanPath, sources[assetId].rawContents);
     }
   }
   
  
positive.code:   }
  
    /// Contents of the file.
    String get contents => _contents;
  
    /// Logger for the current transform.
    ///
  
negative.code: 
    int get hashCode => _proxy.hashCode;
  
    void getContentsToReceiver(Source_ContentReceiver receiver) {
      _proxy.getContentsToReceiver(receiver);
    }
  
    TimestampedData<String> get contents => _proxy.contents;
  
    String get encoding => _proxy.encoding;
  
  