Fix test for TypeImpl.==

pkg/compiler/lib/src/constant_system_dart.dart

Index: pkg/compiler/lib/src/constant_system_dart.dart
diff --git a/pkg/compiler/lib/src/constant_system_dart.dart b/pkg/compiler/lib/src/constant_system_dart.dart
index bcbfd307410bfe4e25b71fe7e1f5168c3146e5eb..f140cf50b07d93a9e3c49e3b18da4c3fd859d3a5 100644
--- a/pkg/compiler/lib/src/constant_system_dart.dart
+++ b/pkg/compiler/lib/src/constant_system_dart.dart
@@ -428,7 +428,11 @@ class DartConstantSystem extends ConstantSystem {
 
   @override
   ConstantValue createType(Compiler compiler, DartType type) {
-    return new TypeConstantValue(type, compiler.coreTypes.typeType);
+    // TODO(johnniwinther): Change the `Type` type to
+    // `compiler.coreTypes.typeType` and check the backend specific value in
+    // [checkConstMapKeysDontOverrideEquals] in 'members.dart'.
+    return new TypeConstantValue(type,
+        compiler.backend.typeImplementation.computeType(compiler));
   }
 
   bool isInt(ConstantValue constant) => constant.isInt;