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

tests/language/implied_interface_test.dart

Index: tests/language/implied_interface_test.dart
diff --git a/tests/language/implied_interface_test.dart b/tests/language/implied_interface_test.dart
index 3779ef5600866c171258e5473b886ea513cc40b7..f565038568c1ed94e4e78ded32274c5141254ff4 100644
--- a/tests/language/implied_interface_test.dart
+++ b/tests/language/implied_interface_test.dart
@@ -34,13 +34,13 @@ main() {
   try {
     c1.foo;
     Expect.fail('expected a NoSuchMethodException');
-  } catch (NoSuchMethodException ex) {
+  } on NoSuchMethodException catch (ex) {
     // Expected error.
   }
   try {
     c2.foo;
     Expect.fail('expected a NoSuchMethodException');
-  } catch (NoSuchMethodException ex) {
+  } on NoSuchMethodException catch (ex) {
     // Expected error.
   }
   Expect.equals(true, c1 is BaseClass);