$scope.test = $location.search().test;

function persistMod($scope, $window) {

$scope.$watch(function (){
  return $window.test;
}, function(v) {
if(v == undefined ){}else{
  if($scope.test !== v) {
     $scope.test = v;
  }
}
});

$scope.$watch('test', function(v) {
  if($window.test !== v) {
     $window.test = v;
  }
});

$scope.$watch(function (){
   return $window.test2;
}, function(v) {
if(v == undefined ){}else{
  if($scope.test2 !== v) {
     $scope.test2 = v;
  }
}
});

 $scope.$watch('test2', function(v) {
  if($window.test2 !== v) {
     $window.test2 = v;
  }
});
}

persistMod($scope, $window);

$location.search({mod1: $scope.test, mod2: $scope.test2});