Fix various inheritance bugs

tests/language/language_dart2js.status

 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 [ $compiler == dart2js || $compiler == dart2dart ]
 class_literal_test/01: Fail # Class literals are expression now; delete this test.
 class_literal_test/02: Fail # Class literals are expression now; delete this test.
 class_literal_test/05: Fail # Class literals are expression now; delete this test.
 class_literal_test/06: Fail # Class literals are expression now; delete this test.
 class_literal_test/07: Fail # Class literals are expression now; delete this test.
@@ skipping 243 matching lines @@
 duplicate_implements_test/03: Fail # Negative language test.
 duplicate_implements_test/04: Fail # Negative language test.
 factory2_negative_test: Fail # Negative language test.
 factory3_negative_test: Fail # Negative language test.
 factory_negative_test: Fail # Negative language test.
 field2_negative_test: Fail # Negative language test.
 field3_negative_test: Fail # Negative language test.
 field4_negative_test: Fail # Negative language test.
 field5_negative_test: Fail # Negative language test.
 field6a_negative_test: Fail # Negative language test.
-field7a_negative_test: Fail # Negative language test.
 final_for_in_variable_test/01: Fail # Negative language test
 final_param_negative_test: Fail # Negative language test.
 final_var_negative_test: Fail # Negative language test.
 instantiate_type_variable_negative_test: Pass  # For the wrong reason.
 interface_factory3_negative_test: Fail # Negative language test.
 interface_factory_constructor_negative_test: Fail # Negative language test.
 interface_static_method_negative_test: Fail # Negative language test.
 list_literal1_negative_test: Fail # Negative language test.
 list_literal2_negative_test: Fail # Negative language test.
 map_literal1_negative_test: Fail # Negative language test.
 map_literal2_negative_test: Fail # Negative language test.
 non_const_super_negative_test: Fail # Negative language test.
 number_identifier_negative_test: Fail # Negative language test.
 operator1_negative_test: Fail # Negative language test.
-override_field_test/04: Fail # Broken test.
 prefix16_test: Fail
 prefix18_negative_test: Fail # Negative language test.
 prefix20_negative_test: Fail # Negative language test.
 prefix23_negative_test: Fail # Negative language test.
 pseudo_kw_illegal_test/03: Fail # Negative language test.
 pseudo_kw_illegal_test/14: Fail # Negative language test.
 scope_negative_test: Fail # Negative language test.
 setter_declaration2_negative_test: Fail # Negative language test.
 setter_declaration_negative_test: Fail # Negative language test.
 static_field_test/01: Fail # Negative language test.
@@ skipping 73 matching lines @@
 [ $runtime == opera ]
 call_through_null_getter_test: Fail
 closure3_test: Fail
 execute_finally3_test: Fail
 method_invocation_test: Fail
 null_pointer_exception_test: Fail
 stack_overflow_test: Fail
 string_interpolate_npe_test: Fail
 closure_call_wrong_argument_count_negative_test: Skip
 label_test: Skip