Update Try Dart to new scanner behavior.

dart/site/try/src/interaction_manager.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 trydart.interaction_manager;
 
 import 'dart:html';
 
 import 'dart:convert' show
     JSON;
 
 import 'dart:math' show
     max,
     min;
 
 import 'dart:async' show
     Future;
 
-import 'package:compiler/implementation/scanner/scannerlib.dart'
-  show
+import 'package:compiler/implementation/scanner/scannerlib.dart' show
+    BeginGroupToken,
     EOF_TOKEN,
+    ErrorToken,
     StringScanner,
     Token;
 
 import 'package:compiler/implementation/source_file.dart' show
     StringSourceFile;
 
 import 'compilation.dart' show
     currentSource,
     scheduleCompilation;
 
@@ skipping 646 matching lines @@
   // do          identifier_abcdefghijklmnopqrst
   for (Token token = tokenize(currentText);
        token.kind != EOF_TOKEN;
        token = token.next) {
     int charOffset = token.charOffset;
     int charCount = token.charCount;
 
     if (charOffset < offset) continue; // Happens for scanner errors.
 
     Decoration decoration = editor.getDecoration(token);
+
+    Token follow = token.next;
+    if (token is BeginGroupToken) {
+      follow = token.endGroup.next;
+    }
+    if (follow is ErrorToken) {
+      decoration = editor.getDecoration(follow);
+    }
+
     if (decoration == null) continue;
 
     // Add a node for text before current token.
     trySelection.addNodeFromSubstring(offset, charOffset, nodes);
 
     // Add a node for current token.
     trySelection.addNodeFromSubstring(
         charOffset, charOffset + charCount, nodes, decoration);
 
     offset = charOffset + charCount;
@@ skipping 15 matching lines @@
     StringBuffer buffer = new StringBuffer();
     int selectionOffset = htmlToText(node, buffer, selection);
     Text newNode = new Text('$buffer');
     node.replaceWith(newNode);
     if (selectionOffset != -1) {
       selection.anchorNode = newNode;
       selection.anchorOffset = selectionOffset;
     }
   }
 }