generate super call: insert at caret, fix read only status tracking (IDEA-166864)

java/java-tests/testData/codeInsight/generateSuperMethodCall/afterOverrideInNestedBlock.java

@@ -0,0 +1,12 @@
+class s implements Runnable {
+    public void run() {
+    }
+}
+
+class Over extends s {
+    public void run() {
+        if (true) {
+            super.run();
+        }
+    }
+}