/// <summary>
 /// Check if the existing documentation is invalid.
 /// </summary>
 /// <param name="declaration">the declaration.</param>
 /// <returns>true if the documentation is invalid.</returns>
 private bool ValidDocumentation(PropertyDeclarationSyntax declaration)
 {
     var commentSyntax = declaration.GetDocumentationCommentTriviaSyntax();
     var xmlText = commentSyntax.GetXmlTextSyntax();
     var startingText = this._commentTextFactory.BuildSummaryTextPrefixForProperty(declaration);
     var starts = xmlText.Trim().StartsWith(startingText, StringComparison.CurrentCulture);
     return starts;
 }