Update corelib/ and lib/ to use the new try-catch syntax.

lib/dom/scripts/idlparser_test.dart

 // Copyright (c) 2011, 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('idlparser_test');
 #import('../../../utils/peg/pegparser.dart');
 #source('idlparser.dart');
 #source('idlrenderer.dart');
 
 main() {
@@ skipping 50 matching lines @@
 """);
 }
 
 
 
 show(grammar, rule, input) {
   print('show: "$input"');
   var ast;
   try {
     ast = grammar.parse(rule, input);
-  } catch (var exception) {
+  } catch (exception) {
     if (exception is ParseError)
       ast = exception;
     else
       throw;
   }
   print('${printList(ast)}');
   print(render(ast));
 }
 
 void check(grammar, rule, input, expected) {
   // If [expected] is String then the result is coerced to string.
   // If [expected] is !String, the result is compared directly.
   print('check: "$input"');
   var ast;
   try {
     ast = grammar.parse(rule, input);
-  } catch (var exception) {
+  } catch (exception) {
     ast = exception;
   }
 
   var formatted = ast;
   if (expected is String)
     formatted = printList(ast);
 
   Expect.equals(expected, formatted, "parse: $input");
 }
 
 // Prints the list in [1,2,3] notation, including nested lists.
 void printList(item) {
   if (item is List) {
     StringBuffer sb = new StringBuffer();
     sb.add('[');
     var sep = '';
     for (var x in item) {
       sb.add(sep);
       sb.add(printList(x));
       sep = ',';
     }
     sb.add(']');
     return sb.toString();
   }
   if (item == null)
     return 'null';
   return item.toString();
 }