[解決済み】Angularjsのng-modelがng-ifの中で動かない。

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.min.js"></script>

<script>
    function main($scope) {
        $scope.testa = false;
        $scope.testb = false;
        $scope.testc = false;
        $scope.obj = {test: false};
    }
</script>

<div ng-app >
    <div ng-controller="main">
        
        Test A: {{testa}}<br />
        Test B: {{testb}}<br />
        Test C: {{testc}}<br />
        {{obj.test}}
        
        <div>
            testa (without ng-if): <input type="checkbox" ng-model="testa" />
        </div>
        <div ng-if="!testa">
            testb (with ng-if): <input type="checkbox" ng-model="testb" /> {{testb}}
        </div>
        <div ng-if="!someothervar">
            testc (with ng-if): <input type="checkbox" ng-model="testc" />
        </div>
        <div ng-if="!someothervar">
            object (with ng-if): <input type="checkbox" ng-model="obj.test" />
        </div>
        
    </div>
</div>