Update language.status and rewrite two tests

tests/language/language_dart2js.status

Index: tests/language/language_dart2js.status
diff --git a/tests/language/language_dart2js.status b/tests/language/language_dart2js.status
index 113b66810ed2e747e7f8f1a3786956182735eb0c..3cc4e66df12faa8a264d5ce9cec0acf5c80d90d7 100644
--- a/tests/language/language_dart2js.status
+++ b/tests/language/language_dart2js.status
@@ -174,11 +174,15 @@ interface_cycle_negative_test: Fail, OK # Bad test: assumes eager loading.
 #
 # The following tests are all negative tests that should be fixed.
 #
-abstract_syntax_test/01: Fail # Negative language test.
-const_constructor_syntax_test/04: Fail # Negative language test.
-const_syntax_test/04: Fail # Negative language test.
-constructor2_negative_test: Fail # Negative language test.
-constructor_return_negative_test: Fail # Negative language test.
+abstract_syntax_test/01: Fail # Issue 12898
+const_constructor_syntax_test/04: Fail # Issue 12900
+const_syntax_test/01: Fail # Issue 12932
+const_syntax_test/02: Fail # Issue 12932
+const_syntax_test/03: Fail # Issue 12932
+const_syntax_test/04: Fail # Issue 12932
+constructor9_test/01: Fail # Issue 12934
+constructor_return_test/01: Fail # Issue 12937
+constructor_return_test/02: Fail # Issue 12937
 constructor_return_with_arrow_negative_test: Fail # Negative language test.
 constructor_return_with_init_and_arrow_negative_test: Fail # Negative language test.
 constructor_return_with_init_negative_test: Fail # Negative language test.
@@ -210,9 +214,6 @@ final_syntax_test/01: Fail # Missing error for uninitialized final field.
 final_syntax_test/02: Fail # Missing error for uninitialized final field.
 final_syntax_test/03: Fail # Missing error for uninitialized final field.
 final_syntax_test/04: Fail # Missing error for uninitialized final field.
-const_syntax_test/01: Fail # Missing error for uninitialized final field.
-const_syntax_test/02: Fail # Missing error for uninitialized final field.
-const_syntax_test/03: Fail # Missing error for uninitialized final field.
 
 canonical_const2_test: Fail, OK # Dart2js only has doubles.
 
@@ -325,16 +326,19 @@ compile_time_constant_arguments_test/02: Fail # Issue 5519
 compile_time_constant_arguments_test/03: Fail # Issue 5519
 compile_time_constant_arguments_test/05: Fail # Issue 5519
 compile_time_constant_arguments_test/06: Fail # Issue 5519
-const_constructor_syntax_test/04: Fail # Issue 5519
-const_syntax_test/01: Fail # Issue 5519
-const_syntax_test/02: Fail # Issue 5519
-const_syntax_test/03: Fail # Issue 5519
-const_syntax_test/04: Fail # Issue 5519
-const_syntax_test/05: Fail # Issue 5519
-const_syntax_test/06: Fail # Issue 5519
-const_syntax_test/07: Fail # Issue 5519
-const_syntax_test/08: Fail # Issue 5519
-const_syntax_test/10: Fail # Issue 5519
+const_constructor_syntax_test/04: Fail # Issue 12901
+const_syntax_test/01: Fail # Issue 12933
+const_syntax_test/02: Fail # Issue 12933
+const_syntax_test/03: Fail # Issue 12933
+const_syntax_test/04: Fail # Issue 12933
+const_syntax_test/05: Fail # Issue 12933
+const_syntax_test/06: Fail # Issue 12933
+const_syntax_test/07: Fail # Issue 12933
+const_syntax_test/08: Fail # Issue 12933
+const_syntax_test/10: Fail # Issue 12933
+constructor9_test/01: Fail # Issue 12935
+constructor_return_test/01: Fail # Issue 12938
+constructor_return_test/02: Fail # Issue 12938
 constructor_named_arguments_test/01: Fail # Issue 5519
 final_syntax_test/01: Fail # Issue 5519
 final_syntax_test/02: Fail # Issue 5519
@@ -356,7 +360,7 @@ interface_cycle_negative_test: Fail, OK # Bad test: assumes eager loading.
 # Common problems with dart2js.  In illegal family, invalid
 # declarations are simply not parsed.  In pseudo kw dart2js
 # chokes on things like typedef(x) => "typedef $x" and alike.
-abstract_syntax_test/01: Fail
+abstract_syntax_test/01: Fail # Issue 12899
 pseudo_kw_test: Fail
 # external keyword is not yet supported by dart2js/dart2dart.
 external_test/*: Skip