Implement operator-is for interfaces' supertypes and String's supertypes. Also, improve stack trace…

dart/tests/co19/co19-leg.status

Index: dart/tests/co19/co19-leg.status
diff --git a/dart/tests/co19/co19-leg.status b/dart/tests/co19/co19-leg.status
index 810020b9d7b8c13fe1502d4d27e80ac25f95e9d0..0b9fddd23d9878b7f412db276faddf6458534784 100644
--- a/dart/tests/co19/co19-leg.status
+++ b/dart/tests/co19/co19-leg.status
@@ -161,6 +161,7 @@ Language/06_Functions/06_Functions_A03_t01: Fail # Cannot find value
 Language/06_Functions/2_Formal_Parameters/2_Named_Optional_Formals_A01_t01: Fail # CompileTimeConstantHandler non-primitive list-entries not implemented
 Language/07_Classes/7_Static_Variables_A04_t01: Fail # SsaBuilder.visitContinueStatement not implemented
 Language/07_Classes/8_Superclasses/1_Inheritance_and_Overriding_A02_t03: Fail # SsaBuilder.visitIdentifier on non-this
+Language/13_Types/4_Interface_Types_A07_t03: Fail # SsaBuilder.visitContinueStatement not implemented
 Language/13_Types/4_Interface_Types_A09_t01: Fail # Cannot find value
 Language/13_Types/5_Function_Types_A02_t03: Fail # Cannot find value
 Language/13_Types/5_Function_Types_A02_t05: Fail # Cannot find value
@@ -297,7 +298,6 @@ LibTest/core/Set/some_A01_t03: Fail # Cannot find value
 LibTest/core/int/toRadixString_A01_t01: Fail # Expect.stringEquals(expected: <6A>", <6a>) fails
 
 
-
 LibTest/core/List/List_A01_t02: Fail # Fixed length array.
 LibTest/core/List/addAll_A02_t01: Fail # Fixed length array.
 LibTest/core/List/add_A02_t01: Fail # Fixed length array.
@@ -309,12 +309,9 @@ LibTest/core/List/removeRange_A02_t01: Fail # Fixed length array.
 LibTest/core/List/addLast_A02_t01: Fail # Fixed length array.
 
 
-LibTest/core/Date/compareTo_A01_t01: Fail # Fail is Comparable test.
 LibTest/core/Date/timeZone_A01_t01: Fail # Should throw NoSuchMethodException.
 LibTest/core/Date/value_A01_t01: Fail # Should throw NoSuchMethodException.
-LibTest/core/Duration/compareTo_A01_t01: Fail # Fail is Comparable test.
 LibTest/core/Math/parseDouble_A02_t01: Fail # TODO(ahe): Reject bad values.
-LibTest/core/String/String_class_A03_t01: Fail # Implement is-checks.
 LibTest/core/Queue/iterator_A01_t01: Fail # Implement is-checks.
 
 
@@ -338,10 +335,7 @@ Language/07_Classes/1_Instance_Methods/1_Abstract_Methods_A02_t02: Fail # Expect
 Language/07_Classes/4_Instance_Variables_A02_t01: Fail # Expect.equals(expected: <bar>, actual: <null>) fails.
 Language/07_Classes/4_Instance_Variables_A03_t01: Fail # Expect.equals(expected: <bar>, actual: <null>) fails.
 Language/07_Classes/5_Constructors/1_Generative_Constructors_A11_t01: Fail # Expect.equals(expected: <1>, actual: <null>, 'Instance variable should already be initialized!') fails.
-Language/13_Types/4_Interface_Types_A02_t01: Fail # Expect.isTrue(false) fails.
-Language/13_Types/4_Interface_Types_A04_t02: Fail # Expect.isTrue(false) fails.
 Language/13_Types/4_Interface_Types_A05_t03: Fail # Expect.isTrue(false) fails.
-Language/13_Types/4_Interface_Types_A11_t04: Fail # Expect.isTrue(false) fails.
 Language/13_Types/4_Interface_Types_A12_t09: Fail # Expect.isFalse(true) fails.
 Language/13_Types/4_Interface_Types_A12_t12: Fail # Expect.isFalse(true) fails.
 Language/13_Types/4_Interface_Types_A12_t13: Fail # Expect.isFalse(true) fails.