Update almost all tests (except co19) to use the new try-catch syntax.

tests/language/throw7_negative_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.
 // Dart test program for testing throw statement
 
 class MyException1 {
   const MyException1([String message = "1"]) : message_ = message;
   final String message_;
 }
 
 class Helper {
   Helper() : i = 0 { }
 
   int f1() {
     int j = 0;
     try {
       j = i;
-    } catch (var exception) {
+    } catch (exception) {
       i = i + 100;
       print(exception.message_);
     }
     // Since there is a generic 'catch all' statement preceding this
     // we expect to get a dead code error/warning over here.
-    catch (MyException1 exception) {
+    on MyException1 catch (exception) {
       i = i + 100;
       print(exception.message_);
     }
     finally {
       i = i + 1000;
     }
     return i;
   }
 
   int i;
 }
 
 class Throw7NegativeTest {
   static testMain() {
     new Helper().f1();
   }
 }
 
 main() {
   Throw7NegativeTest.testMain();
 }