fix(select): update option labels when model changes

Closes #9025

Author: btford

src/ng/directive/select.js

@@ -404,6 +404,19 @@ var selectDirective = ['$compile', '$parse', function($compile,   $parse) {
         ctrl.$render = render;
 
         scope.$watchCollection(valuesFn, render);
+        scope.$watchCollection(function () {
+          var locals = {},
+              values = valuesFn(scope);
+          if (values) {
+            var toDisplay = new Array(values.length);
+            for (var i = 0, ii = values.length; i < ii; i++) {
+              locals[valueName] = values[i];
+              toDisplay[i] = displayFn(scope, locals);
+            }
+            return toDisplay;
+          }
+        }, render);
+
         if ( multiple ) {
           scope.$watchCollection(function() { return ctrl.$modelValue; }, render);
         }

test/ng/directive/selectSpec.js

@@ -871,6 +871,26 @@ describe('select', function() {
         expect(element.val()).toEqual('1');
       });
 
+      it('should update options in the DOM', function() {
+        compile(
+          '<select ng-model="selected" ng-options="item.id as item.name for item in values"></select>'
+        );
+
+        scope.$apply(function() {
+          scope.values = [{id: 10, name: 'A'}, {id: 20, name: 'B'}];
+          scope.selected = scope.values[0].id;
+        });
+
+        scope.$apply(function() {
+          scope.values[0].name = 'C';
+        });
+
+        var options = element.find('option');
+        expect(options.length).toEqual(2);
+        expect(sortedHtml(options[0])).toEqual('<option value="0">C</option>');
+        expect(sortedHtml(options[1])).toEqual('<option value="1">B</option>');
+      });
+
 
       it('should bind to object key', function() {
         createSelect({