introduce constant: create subclass when it is not possible to place the constant inside the class (IDEA-86965)

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

@@ -0,0 +1,6 @@
+enum TestEnum {
+  ONE("te<caret>stString");
+
+  TestEnum(String str) {
+  }
+}

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

@@ -0,0 +1,10 @@
+enum TestEnum {
+  ONE(Constants.xxx);
+
+  TestEnum(String str) {
+  }
+
+    private class Constants {
+        public static final String xxx = "testString";
+    }
+}