fix(popup): make popups play nice with other async popups

Closes #4118

Author: zittix

Diff for: js/angular/service/popup.js

@@ -403,6 +403,8 @@ function($ionicTemplateLoader, $ionicBackdrop, $q, $timeout, $rootScope, $ionicB
           popupStack.splice(index, 1);
         }
 
+        popup.remove();
+
         if (popupStack.length > 0) {
           popupStack[popupStack.length - 1].show();
         } else {
@@ -418,7 +420,6 @@ function($ionicTemplateLoader, $ionicBackdrop, $q, $timeout, $rootScope, $ionicB
           ($ionicPopup._backButtonActionDone || noop)();
         }
 
-        popup.remove();
 
         return result;
       });