Mark language/bad_raw_string_test/{none,03} as failing on dartk.

tests/language/language_kernel.status

Index: tests/language/language_kernel.status
diff --git a/tests/language/language_kernel.status b/tests/language/language_kernel.status
index d74416d5800fae4c8f423a7a5b344397d922f22e..272197f01753bda9ffcfc47c7ad83acfb754aac8 100644
--- a/tests/language/language_kernel.status
+++ b/tests/language/language_kernel.status
@@ -231,6 +231,10 @@ ct_const2_test: Pass, CompileTimeError  # VMOptions=--compile-all causes us to h
 [ $compiler == dartk || $compiler == dartkp ]
 runtime_type_function_test: RuntimeError
 
+[ $compiler == dartkp ]
+bad_raw_string_test/none: Skip # Issue 28680
+bad_raw_string_test/03: Skip # Issue 28680
+
 # Triaged checked mode failures
 [ ($compiler == dartk || $compiler == dartkp) && $checked ]
 language/regress_22728_test: Fail # Dartk Issue 28498