Added ability to invoke accountsModel.refreshRegistration() from descendants of CallsModel

Author: siprix

siprix_voip_sdk/lib/accounts_model.dart

@@ -594,6 +594,7 @@ class AccountsModel extends ChangeNotifier implements IAccountsModel {
   }
 
   /// Refresh registration of the all existing accounts (with default or specified regExpire>0)
+  @override
   Future<void> refreshRegistration() async {
     try {
       for(AccountModel acc in _accounts) {

siprix_voip_sdk/lib/calls_model.dart

@@ -600,6 +600,7 @@ class CallsModel extends ChangeNotifier {
   CallModel operator [](int i) => _callItems[i]; // get
 
   @protected List<CallModel> get callItems => _callItems;
+  @protected IAccountsModel  get accountsModel => _accountsModel;
 
   /// Returns id of the switched call (or kEmptyCallId when there are no calls)
   int get switchedCallId => _switchedCallId;

siprix_voip_sdk/lib/siprix_voip_sdk.dart

@@ -482,6 +482,8 @@ abstract interface class IAccountsModel {
   bool hasSecureMedia(int accId);
   ///Returns true if account with specified id has 'upgradeToVideo' set to 'RecvOnly'
   bool isUpgradeToVideoModeRecvOnly(String uri);
+  ///Refresh registration of the all accounts
+  void refreshRegistration();
 }