fix(typeahead): use $setViewValue on blur

Use $setViewValue instead of setting directly $viewValue to '', to make new value go through validators.

Closes angular-ui#5769
Fixes angular-ui#5694

src/typeahead/test/typeahead.spec.js

@@ -315,6 +315,21 @@ describe('typeahead tests', function() {
       expect($scope.form.input.$error.parse).toBeFalsy();
     });
 
+    it('should go through other validators after blur for typeahead-editable="false"', function () {
+        var element = prepareInputEl(
+        '<div><form name="form">' +
+          '<input name="input" ng-model="result" uib-typeahead="item for item in source | filter:$viewValue" typeahead-editable="false" required>' +
+        '</form></div>');
+        var inputEl = findInput(element);
+
+        changeInputValueTo(element, 'not in matches');
+        expect($scope.result).toEqual(undefined);
+        expect(inputEl.val()).toEqual('not in matches');
+        inputEl.blur(); // input loses focus
+        expect($scope.result).toEqual(undefined);
+        expect($scope.form.input.$error.required).toBeTruthy();
+    });
+
     it('should clear view value when no value selected for typeahead-editable="false" typeahead-select-on-blur="false"', function () {
         var element = prepareInputEl('<div><input ng-model="result" uib-typeahead="item for item in source | filter:$viewValue" typeahead-editable="false" typeahead-select-on-blur="false"></div>');
         var inputEl = findInput(element);

src/typeahead/typeahead.js

@@ -441,7 +441,7 @@ angular.module('ui.bootstrap.typeahead', ['ui.bootstrap.debounce', 'ui.bootstrap
         });
       }
       if (!isEditable && modelCtrl.$error.editable) {
-        modelCtrl.$viewValue = '';
+        modelCtrl.$setViewValue();
         // Reset validity as we are clearing
         modelCtrl.$setValidity('editable', true);
         modelCtrl.$setValidity('parse', true);