[mdv] getTeminatorAt recurses infinitely if template is its own terminator

pkg/mdv/test/template_element_test.dart

 // Copyright (c) 2013, 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 template_element_test;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:html';
 import 'dart:math' as math;
@@ skipping 1331 matching lines @@
     deliverChanges(m);
     expect(div.nodes.length, 7);
     expect(div.nodes[5].text, 'Name: Leela');
 
     m[sym('friend')] = toSymbols({'name': 'Leela'});
     deliverChanges(m);
     expect(div.nodes.length, 5);
     expect(div.nodes[3].text, 'Name: Leela');
   });
 
+  observeTest('Template - Self is terminator', () {
+    var div = createTestHtml(
+        '<template repeat>{{ foo }}'
+          '<template bind></template>'
+        '</template>');
+
+    var m = toSymbols([{ 'foo': 'bar' }]);
+    recursivelySetTemplateModel(div, m);
+    performMicrotaskCheckpoint();
+
+    m.add(toSymbols({ 'foo': 'baz' }));
+    recursivelySetTemplateModel(div, m);
+    performMicrotaskCheckpoint();
+
+    expect(div.nodes.length, 5);
+    expect(div.nodes[1].text, 'bar');
+    expect(div.nodes[3].text, 'baz');
+  });
+
   observeTest('RecursiveRef', () {
     var div = createTestHtml(
         '<template bind>'
           '<template id=src>{{ foo }}</template>'
           '<template bind ref=src></template>'
         '</template>');
 
     var m = toSymbols({'foo': 'bar'});
     recursivelySetTemplateModel(div, m);
     performMicrotaskCheckpoint();
@@ skipping 335 matching lines @@
       k = k is String ? sym(k) : _deepToSymbol(k);
       result[k] = _deepToSymbol(v);
     });
     return result;
   }
   if (value is Iterable) {
     return value.map(_deepToSymbol).toList();
   }
   return value;
 }