code: private OriginalMapping getOriginalMappingForEntry(Entry entry) {
      if (entry.getSourceFileId() == UNMAPPED) {
        return null;
      } else {
        // Adjust the line/column here to be start at 1.
        Builder x = OriginalMapping.newBuilder()
          .setOriginalFile(sources[entry.getSourceFileId()])
          .setLineNumber(entry.getSourceLine() + 1)
          .setColumnPosition(entry.getSourceColumn() + 1);
        if (entry.getNameId() != UNMAPPED) {
          x.setIdentifier(names[entry.getNameId()]);
        }
        return x.build();
      }
    }
docs: Creates an "OriginalMapping" object for the given entry object.