Add method for getting all classifiers with given name from the scope

compiler/frontend/serialization/src/org/jetbrains/jet/descriptors/serialization/descriptors/DeserializedMemberScope.java

@@ -160,6 +160,13 @@ public abstract class DeserializedMemberScope implements JetScope {
         return getClassDescriptor(name);
     }
 
+    @NotNull
+    @Override
+    public final Collection<ClassifierDescriptor> getClassifiers(@NotNull Name name) {
+        ClassifierDescriptor classifier = getClassifier(name);
+        return classifier != null ? Collections.singleton(classifier) : Collections.<ClassifierDescriptor>emptyList();
+    }
+
     @Nullable
     protected abstract ClassifierDescriptor getClassDescriptor(@NotNull Name name);