Only set types of conditional expressions in strong mode.

pkg/front_end/testcases/rasta/issue_000039.dart.direct.expect

Index: pkg/front_end/testcases/rasta/issue_000039.dart.direct.expect
diff --git a/pkg/front_end/testcases/rasta/issue_000039.dart.direct.expect b/pkg/front_end/testcases/rasta/issue_000039.dart.direct.expect
index 1df3f50483fa88ca0d9b296ad154023b69a4649e..116a7218bf634f14e6b3afddfb4ef40a190c8327 100644
--- a/pkg/front_end/testcases/rasta/issue_000039.dart.direct.expect
+++ b/pkg/front_end/testcases/rasta/issue_000039.dart.direct.expect
@@ -1,5 +1,13 @@
 library;
 import self as self;
+import "dart:core" as core;
 
-static method main() → dynamic
-  throw "pkg/front_end/testcases/rasta/issue_000039.dart:10:3: Error: Expected an expression, but got '}'.\n  }\n  ^";
+class A extends core::Object {
+  field dynamic a;
+  constructor •() → dynamic
+    : invalid-initializer;
+}
+class B extends self::A {
+  constructor •() → self::B
+    : super self::A::•();
+}