extract constant: allow class-constants to be used from enum constant initializer outside argument list (IDEA-161237)

java/java-tests/testData/refactoring/introduceConstant/FromEnumConstantInitializer2.java

@@ -0,0 +1,9 @@
+
+enum Foo {
+
+  FOO1 {
+    public String bar() {
+      return <selection>"bar"</selection>;
+    }
+  }
+}