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

tests/language/execute_finally7_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 execution of finally blocks after an exception
 // is thrown from inside a local function capturing a variable.
 
 
 class MyException {
   const MyException(String message) : message_ = message;
   final String message_;
@@ skipping 15 matching lines @@
           return j;
         };
         if (i == 0) {
           b = a[i];
         }
         i++;
       }
       for(int i = 0; i < 10; i++) {
         a[i]();
       }
-    } catch (MyException exception) {
+    } on MyException catch (exception) {
       k += 100;
       print(exception.message_);
       b();
     } finally {
       k += 1000;
       b();
     }
     return k;
   }
 }
 
 class ExecuteFinally7Test {
   static testMain() {
     Expect.equals(1171, Helper.f1(1));
   }
 }
 
 main() {
   ExecuteFinally7Test.testMain();
 }