Change Signature: Support conversion between extension and non-extension functions

idea/testData/refactoring/changeSignature/AddReceiverToGenericsWithOverridesBefore.1.java

@@ -0,0 +1,18 @@
+interface J<A> extends T<A> {
+    @Override
+    <B> int foofoofoo(A a, B b);
+}
+
+abstract class J1<X> implements J<U<X>> {
+    @Override
+    public <C> int foofoofoo(U<X> xu, C c) {
+        throw new UnsupportedOperationException();
+    }
+}
+
+abstract class J2 extends J1<String> {
+    @Override
+    public <C> int foofoofoo(U<String> xu, C c) {
+        throw new UnsupportedOperationException();
+    }
+}