Fix for 11987.

editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/type/DynamicTypeImpl.java

Index: editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/type/DynamicTypeImpl.java
diff --git a/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/type/DynamicTypeImpl.java b/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/type/DynamicTypeImpl.java
index cd8d22452e019a7e0322a162faeecccba7109afa..966ac29ce4aa5b14efc93743bf449099d959fee0 100644
--- a/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/type/DynamicTypeImpl.java
+++ b/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/type/DynamicTypeImpl.java
@@ -17,6 +17,8 @@ import com.google.dart.engine.internal.element.DynamicElementImpl;
 import com.google.dart.engine.scanner.Keyword;
 import com.google.dart.engine.type.Type;
 
+import java.util.Set;
+
 /**
  * The unique instance of the class {@code DynamicTypeImpl} implements the type {@code dynamic}.
  * 
@@ -56,22 +58,6 @@ public class DynamicTypeImpl extends TypeImpl {
   }
 
   @Override
-  public boolean isMoreSpecificThan(Type type, boolean withDynamic) {
-    // T is S
-    if (this == type) {
-      return true;
-    }
-    // else
-    return withDynamic;
-  }
-
-  @Override
-  public boolean isSubtypeOf(Type type) {
-    // dynamic is a subtype of all types
-    return true;
-  }
-
-  @Override
   public boolean isSupertypeOf(Type type) {
     // dynamic is a supertype of all types
     return true;
@@ -87,4 +73,21 @@ public class DynamicTypeImpl extends TypeImpl {
     }
     return this;
   }
+
+  @Override
+  protected boolean internalIsMoreSpecificThan(Type type, boolean withDynamic,
+      Set<TypePair> visitedTypePairs) {
+    // T is S
+    if (this == type) {
+      return true;
+    }
+    // else
+    return withDynamic;
+  }
+
+  @Override
+  protected boolean internalIsSubtypeOf(Type type, Set<TypePair> visitedTypePairs) {
+    //dynamic is a subtype of all types
+    return true;
+  }
 }