Enqueue superclasses instead of supertypes.

pkg/compiler/lib/src/elements/common.dart

Index: pkg/compiler/lib/src/elements/common.dart
diff --git a/pkg/compiler/lib/src/elements/common.dart b/pkg/compiler/lib/src/elements/common.dart
index 6c4352a3ed10a338555c15fa627abd8fe890c8b7..9d0458229d63dbeddfc38b4cb521c2d630306382 100644
--- a/pkg/compiler/lib/src/elements/common.dart
+++ b/pkg/compiler/lib/src/elements/common.dart
@@ -415,13 +415,7 @@ abstract class ClassElementCommon implements ClassElement {
     return false;
   }
 
-  /**
-   * Returns true if [this] is a subclass of [cls].
-   *
-   * This method is not to be used for checking type hierarchy and
-   * assignments, because it does not take parameterized types into
-   * account.
-   */
+  @override
   bool isSubclassOf(ClassElement cls) {
     // Use [declaration] for both [this] and [cls], because
     // declaration classes hold the superclass hierarchy.
@@ -436,6 +430,11 @@ abstract class ClassElementCommon implements ClassElement {
     MemberSignature member = lookupInterfaceMember(Names.call);
     return member != null && member.isMethod ? member.type : null;
   }
+
+  @override
+  bool get isNamedMixinApplication {
+    return isMixinApplication && !isUnnamedMixinApplication;
+  }
 }
 
 abstract class FunctionSignatureCommon implements FunctionSignature {