restore class by index in target file for top level classes

EA-36372 - assert: CreateSubclassAction$.templateFinished

java/java-tests/testData/codeInsight/createSubclass/imports/after/Subclass.java

@@ -0,0 +1,4 @@
+import java.util.List;
+
+public class Subclass<E extends List<String>> extends Superclass<E> {
+}

java/java-tests/testData/codeInsight/createSubclass/imports/after/Superclass.java

@@ -0,0 +1,2 @@
+class Superclass<E extends java.util.List<String>> {
+}

java/java-tests/testData/codeInsight/createSubclass/imports/before/Superclass.java

@@ -0,0 +1,2 @@
+class Superclass<E extends java.util.List<String>> {
+}