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

tests/language/prefix16_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.
 //
 // Unresolved imported symbols are handled differently in production mode and
 // check modes. In this test, the function myFunc is malformed, because
 // lib12.Library13 is not resolved.
 // In checked mode, the assignment type check throws a run time type error.
 // In production, no assignment type checks are performed.
 
 #library("Prefix16NegativeTest.dart");
 #import("library12.dart", prefix:"lib12");
 
 typedef lib12.Library13 myFunc(lib12.Library13 param);
 
 isCheckedMode() {
   try {
     var i = 1;
     String s = i;
     return false;
-  } catch(var e) {
+  } catch (e) {
     return true;
   }
 }
 
 main() {
   {
     bool got_type_error = false;
     try {
       myFunc i = 0;
-    } catch (TypeError error) {
+    } on TypeError catch (error) {
       got_type_error = true;
     }
     // Type error in checked mode only.
     Expect.isTrue(got_type_error == isCheckedMode());
   }
   {
     bool got_type_error = false;
     try {
       // In production mode, malformed myFunc is mapped to (Dynamic) => Dynamic.
       Expect.isTrue(((int x) => x) is myFunc);
-    } catch (TypeError error) {
+    } on TypeError catch (error) {
       got_type_error = true;
     }
     // Type error in checked mode only.
     Expect.isTrue(got_type_error == isCheckedMode());
   }
 }