Add Capability class.

tests/isolate/isolate.status

Index: tests/isolate/isolate.status
diff --git a/tests/isolate/isolate.status b/tests/isolate/isolate.status
index 0df05ed298edffd85afc7449d632366b82ac174a..ef68ce86d1c15dce633b44be47f99f947980cf57 100644
--- a/tests/isolate/isolate.status
+++ b/tests/isolate/isolate.status
@@ -10,6 +10,7 @@ isolate_stress_test: Fail # Issue 12588: This should be able to pass when we hav
 serialization_test: SkipByDesign # Tests dart2js-specific serialization code
 isolate_throws_test/01: Skip # Issue 12587
 compile_time_error_test/01: Skip # Issue 12587
+capability_test: Fail
 
 [ $compiler == dart2js && $jscl ]
 browser/*: SkipByDesign  # Browser specific tests
@@ -19,6 +20,7 @@ isolate_stress_test: Pass, Crash # Issue 14438
 
 [ $compiler == dart2js ]
 serialization_test: RuntimeError # Issue 1882, tries to access class TestingOnly declared in isolate_patch.dart
+capability_test: Fail
 
 [ $compiler == dart2js && $runtime == ie9 ]
 browser/typed_data_message_test: Fail # Issue 12624