suggest only superclass elements for "super."

pkg/analysis_server/test/services/completion/prefixed_element_contributor_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library test.services.completion.invocation;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/completion/dart_completion_manager.dart';
@@ skipping 505 matching lines @@
 class Derived extends Base implements Interface {
 }
 void test(Derived d) {
   d.^
 }
 ''');
     return computeFull((bool result) {
       assertSuggestMethod('f', 'Base', 'void');
     });
   }
+
+  test_super() {
+    // SimpleIdentifier  MethodInvocation  ExpressionStatement
+    addTestSource('''
+class C2 {
+  int fi2;
+  static int fs2;
+  m() {}
+  mi2() {}
+  static ms2() {}
 }
+class C1 extends C2 {
+  int fi1;
+  static int fs1;
+  m() {super.^}
+  mi1() {}
+  static ms1() {}
+}''');
+    return computeFull((bool result) {
+      assertNotSuggested('fi1');
+      assertNotSuggested('fs1');
+      assertNotSuggested('mi1');
+      assertNotSuggested('ms1');
+      assertSuggestInvocationField('fi2', 'int');
+      assertNotSuggested('fs2');
+      assertSuggestInvocationMethod('mi2', 'C2', null);
+      assertNotSuggested('ms2');
+      assertSuggestInvocationMethod('m', 'C2', null);
+    });
+  }
+}