fix #27421, DDC did not generate implicit super calls in some cases

pkg/dev_compiler/test/codegen/language/implicit_super_constructor_test.dart

Index: pkg/dev_compiler/test/codegen/language/implicit_super_constructor_test.dart
diff --git a/tests/language/conflicting_type_variable_and_setter_test.dart b/pkg/dev_compiler/test/codegen/language/implicit_super_constructor_test.dart
similarity index 57%
copy from tests/language/conflicting_type_variable_and_setter_test.dart
copy to pkg/dev_compiler/test/codegen/language/implicit_super_constructor_test.dart
index 2aca0c32b659b1f1f213c4744ab50c6753befbbc..2c31206a2333de074885bc19d799b1c8f45f2035 100644
--- a/tests/language/conflicting_type_variable_and_setter_test.dart
+++ b/pkg/dev_compiler/test/codegen/language/implicit_super_constructor_test.dart
@@ -4,16 +4,17 @@
 
 import "package:expect/expect.dart";
 
-class C<D> {
-  void set D(int value) {
-    field = value;
-  }
+abstract class A {
+  int _x = 42;
+}
+
+abstract class B extends A {}
 
-  int field;
+class C extends B {
+  C() {}
 }
 
 main() {
-  C<int> c = new C<int>();
-  c.D = 1;
-  Expect.equals(c.field, 1);
+  // Regression test for https://github.com/dart-lang/sdk/issues/27421
+  Expect.equals(new C()._x, 42);
 }