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

corelib/src/expect.dart

 // Copyright (c) 2012, 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.
 
 /**
  * Expect is used for tests that do not want to make use of the
  * Dart unit test library - for example, the core language tests.
  * Third parties are discouraged from using this, and should use
  * the expect() function in the unit test library instead for
  * test assertions.
@@ skipping 247 matching lines @@
    * that the correct exception is being thrown.  For example, to check
    * the type of the exception you could write this:
    *
    *     Expect.throws(myThrowingFunction, (e) => e is MyException);
    */
   static void throws(void f(),
                      [_CheckExceptionFn check = null,
                       String reason = null]) {
     try {
       f();
-    } catch (var e) {
+    } catch (e) {
       if (check !== null) {
         Expect.isTrue(check(e));
       }
       return;
     }
     String msg = _getMessage(reason);
     _fail('Expect.throws($msg) fails');
   }
 
   static String _getMessage(String reason)
       => (reason === null) ? "" : ", '$reason'";
 
   static void _fail(String message) {
     throw new ExpectException(message);
   }
 }
 
 typedef bool _CheckExceptionFn(exception);
 
 class ExpectException implements Exception {
   ExpectException(this.message);
   String toString() => message;
   String message;
 }