revert(typeahead): prevent accidental form submission on ENTER

Closes #1298
This reverts commit 253c49f.

src/typeahead/test/typeahead.spec.js

@@ -60,7 +60,6 @@ describe('typeahead tests', function () {
     var e = $.Event("keydown");
     e.which = keyCode;
     inputEl.trigger(e);
-    return e;
   };
 
   //custom matchers
@@ -439,13 +438,6 @@ describe('typeahead tests', function () {
       expect($scope.isLoading).toBeFalsy();
     });
 
-    it('pr 1165 - prevent default on ENTER to avoid accidental form submission', function () {
-      var element = prepareInputEl("<div><input ng-model='result' typeahead='item for item in source | filter:$viewValue'></div>");
-      var e = triggerKeyDown(element, 13);
-
-      expect(e.isDefaultPrevented()).toBeTruthy();
-    });
-
     it('does not close matches popup on click in input', function () {
       var element = prepareInputEl("<div><input ng-model='result' typeahead='item for item in source | filter:$viewValue'></div>");
       var inputEl = findInput(element);

src/typeahead/typeahead.js

@@ -230,9 +230,6 @@ angular.module('ui.bootstrap.typeahead', ['ui.bootstrap.position', 'ui.bootstrap
 
         //typeahead is open and an "interesting" key was pressed
         if (scope.matches.length === 0 || HOT_KEYS.indexOf(evt.which) === -1) {
-          if (evt.which === 13) {
-            evt.preventDefault();
-          }
           return;
         }