feat(modal): pass reason when opened promise rejected

Closes #2978

Author: onjiro

src/modal/modal.js

@@ -458,8 +458,8 @@ angular.module('ui.bootstrap.modal', [])
 
             templateAndResolvePromise.then(function () {
               modalOpenedDeferred.resolve(true);
-            }, function () {
-              modalOpenedDeferred.reject(false);
+            }, function (reason) {
+              modalOpenedDeferred.reject(reason);
             });
 
             return modalInstance;

src/modal/test/modal.spec.js

@@ -231,7 +231,7 @@ describe('$modal', function () {
           ok: function() {return $q.reject('ko');}
         }}
       );
-      expect(modal.opened).toBeRejectedWith(false);
+      expect(modal.opened).toBeRejectedWith('ko');
     });
 
     it('should focus on the element that has autofocus attribute when the modal is open/reopen', function () {