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

tests/language/named_parameters9_negative_test.dart

Index: tests/language/named_parameters9_negative_test.dart
diff --git a/tests/language/named_parameters9_negative_test.dart b/tests/language/named_parameters9_negative_test.dart
index 74a01ee482ed444e10bbaeef473ad77433940971..c348ef5a1a4b17ce83d9a541507a044d9ac85565 100644
--- a/tests/language/named_parameters9_negative_test.dart
+++ b/tests/language/named_parameters9_negative_test.dart
@@ -11,7 +11,7 @@ class NamedParameters9NegativeTest {
   static testMain() {
     try {
       f(10, 25);
-    } catch (var e) {
+    } catch (e) {
       // This is a negative test that should not compile.
       // If it runs due to a bug, catch and ignore exceptions.
     }