TextMimeData constructor
Creates a new text based mime data
with the specified text and the containsHeader information.
Line endings are automatically normalized to CRLF (\r\n) for
RFC 5322 compliance, tolerating bare LF from non-conformant MIME
generators (e.g. Node.js mimetext on Linux which uses os.EOL).
Implementation
TextMimeData(String text, {required bool containsHeader})
: text = _normalizeLineEndings(text),
super(containsHeader: containsHeader) {
_size = this.text.length;
}