Fix type masks for js-interop types.

pkg/compiler/lib/src/js_backend/no_such_method_registry.dart

Index: pkg/compiler/lib/src/js_backend/no_such_method_registry.dart
diff --git a/pkg/compiler/lib/src/js_backend/no_such_method_registry.dart b/pkg/compiler/lib/src/js_backend/no_such_method_registry.dart
index c7918ce83082672c3660d95e53978774713896cd..39abf47d9f728521aef83047bdb1aca87345e49e 100644
--- a/pkg/compiler/lib/src/js_backend/no_such_method_registry.dart
+++ b/pkg/compiler/lib/src/js_backend/no_such_method_registry.dart
@@ -150,7 +150,7 @@ class NoSuchMethodRegistry {
       notApplicableImpls.add(element);
       return NsmCategory.NOT_APPLICABLE;
     }
-    if (_isDefaultNoSuchMethodImplementation(element)) {
+    if (isDefaultNoSuchMethodImplementation(element)) {
       defaultImpls.add(element);
       return NsmCategory.DEFAULT;
     } else if (_hasForwardingSyntax(element)) {
@@ -186,7 +186,7 @@ class NoSuchMethodRegistry {
     }
   }
 
-  bool _isDefaultNoSuchMethodImplementation(FunctionElement element) {
+  bool isDefaultNoSuchMethodImplementation(FunctionElement element) {
     ClassElement classElement = element.enclosingClass;
     return classElement == _compiler.coreClasses.objectClass ||
         classElement == _backend.helpers.jsInterceptorClass ||