fromString method
Implementation
PushRuleKind? fromString(String val) {
final override = {
'content': PushRuleKind.content,
'override': PushRuleKind.override,
'room': PushRuleKind.room,
'sender': PushRuleKind.sender,
'underride': PushRuleKind.underride,
}[val];
// ignore: unnecessary_this
return this.contains(override) ? override : null;
}