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

tests/corelib/index_out_of_range_exception_test.dart

Index: tests/corelib/index_out_of_range_exception_test.dart
diff --git a/tests/corelib/index_out_of_range_exception_test.dart b/tests/corelib/index_out_of_range_exception_test.dart
index 8152579df2125a3d11520ff7b4d9a204c5987965..b052a4ba3ad5443b0a3c08ae5982d04f4f2047f7 100644
--- a/tests/corelib/index_out_of_range_exception_test.dart
+++ b/tests/corelib/index_out_of_range_exception_test.dart
@@ -52,7 +52,7 @@ class IndexOutOfRangeExceptionTest {
     var exception = null;
     try {
       var e = list[index];
-    } catch (IndexOutOfRangeException e) {
+    } on IndexOutOfRangeException catch (e) {
       exception = e;
     }
     Expect.equals(true, exception != null);
@@ -62,7 +62,7 @@ class IndexOutOfRangeExceptionTest {
     var exception = null;
     try {
       list[index] = null;
-    } catch (IndexOutOfRangeException e) {
+    } on IndexOutOfRangeException catch (e) {
       exception = e;
     }
     Expect.equals(true, exception != null);