fixes #27385, implement virtual fields in DDC

pkg/dev_compiler/test/not_yet_strong_tests.dart

Index: pkg/dev_compiler/test/not_yet_strong_tests.dart
diff --git a/pkg/dev_compiler/test/not_yet_strong_tests.dart b/pkg/dev_compiler/test/not_yet_strong_tests.dart
index 3361566c6d9ca0e6b775041daceb29d919a3c730..2544ae8abf73489a4103c9db274e58b0a4cd42e6 100644
--- a/pkg/dev_compiler/test/not_yet_strong_tests.dart
+++ b/pkg/dev_compiler/test/not_yet_strong_tests.dart
@@ -666,7 +666,6 @@ final notYetStrongTests = new HashSet<String>.from([
   'language/field_override_test_01_multi',
   'language/field_override_test_02_multi',
   'language/field_override_test_none_multi',
-  'language/field_test',
   'language/field_type_check_test_01_multi',
   'language/final_field_initialization_order_test',
   'language/final_for_in_variable_test_01_multi',
@@ -1349,12 +1348,10 @@ final notYetStrongTests = new HashSet<String>.from([
   'language/override_inheritance_field_test_33_multi',
   'language/override_inheritance_field_test_33a_multi',
   'language/override_inheritance_field_test_34_multi',
-  'language/override_inheritance_field_test_41_multi',
   'language/override_inheritance_field_test_42_multi',
   'language/override_inheritance_field_test_43_multi',
   'language/override_inheritance_field_test_44_multi',
   'language/override_inheritance_field_test_45_multi',
-  'language/override_inheritance_field_test_46_multi',
   'language/override_inheritance_field_test_47_multi',
   'language/override_inheritance_field_test_48_multi',
   'language/override_inheritance_field_test_49_multi',
@@ -1488,7 +1485,6 @@ final notYetStrongTests = new HashSet<String>.from([
   'language/rewrite_implicit_this_test_01_multi',
   'language/scope_variable_test_01_multi',
   'language/setter_no_getter_call_test_01_multi',
-  'language/setter_override2_test_00_multi',
   'language/setter_override_test_00_multi',
   'language/setter_override_test_01_multi',
   'language/setter_override_test_02_multi',
@@ -1760,10 +1756,8 @@ final notYetStrongTests = new HashSet<String>.from([
   'language/type_promotion_closure_test_02_multi',
   'language/type_promotion_closure_test_03_multi',
   'language/type_promotion_closure_test_04_multi',
-  'language/type_promotion_closure_test_05_multi',
   'language/type_promotion_closure_test_06_multi',
   'language/type_promotion_closure_test_07_multi',
-  'language/type_promotion_closure_test_08_multi',
   'language/type_promotion_closure_test_09_multi',
   'language/type_promotion_closure_test_10_multi',
   'language/type_promotion_closure_test_11_multi',
@@ -1772,7 +1766,6 @@ final notYetStrongTests = new HashSet<String>.from([
   'language/type_promotion_closure_test_14_multi',
   'language/type_promotion_closure_test_15_multi',
   'language/type_promotion_closure_test_16_multi',
-  'language/type_promotion_closure_test_none_multi',
   'language/type_promotion_functions_test_01_multi',
   'language/type_promotion_functions_test_02_multi',
   'language/type_promotion_functions_test_03_multi',
@@ -2137,7 +2130,6 @@ final notYetStrongTests = new HashSet<String>.from([
   'lib/mirrors/initializing_formals_test_none_multi',
   'lib/mirrors/instance_members_easier_test',
   'lib/mirrors/instance_members_test',
-  'lib/mirrors/instance_members_with_override_test',
   'lib/mirrors/intercepted_class_test',
   'lib/mirrors/intercepted_object_test',
   'lib/mirrors/invoke_call_through_getter_previously_accessed_test_named_multi',
@@ -2273,7 +2265,6 @@ final notYetStrongTests = new HashSet<String>.from([
   'language/body_less_constructor_wrong_arg_negative_test',
   'language/bound_closure_equality_test',
   'language/call_test',
-  'language/closure_with_super_field_test',
   'language/const_counter_negative_test',
   'language/const_map4_test',
   'language/const_optional_args_negative_test',
@@ -2303,8 +2294,6 @@ final notYetStrongTests = new HashSet<String>.from([
   'language/function_type_parameter2_negative_test',
   'language/function_type_parameter_negative_test',
   'language/getter_declaration_negative_test',
-  'language/getter_override2_test_00_multi',
-  'language/getters_setters_test',
   'language/import_combinators_negative_test',
   'language/initializing_formal_type_test',
   'language/inst_field_initializer1_negative_test',
@@ -2382,8 +2371,6 @@ final notYetStrongTests = new HashSet<String>.from([
   'language/string_unicode2_negative_test',
   'language/string_unicode3_negative_test',
   'language/string_unicode4_negative_test',
-  'language/super_field_2_test',
-  'language/super_field_test',
   'language/switch1_negative_test',
   'language/switch3_negative_test',
   'language/switch4_negative_test',