message: Add a check for negative line/char in DocumentContentChangeAction translation function
  Fixes
diff: @@ -87,7 +87,8 @@ export class DocumentContentChangeAction extends BaseAction {
  lineOffset === 0
  ? position.character + diffPos.character - originalLeftBoundary.character
  : diffPos.character;
  - return new Position(position.line + lineOffset, char);
  + // TODO: Should we document.validate() this position?
  + return new Position(Math.max(position.line + lineOffset, 0), Math.max(char, 0));
  };
  replaceRange = new Range(translate(change.range.start), translate(change.range.end));
  