convert to instance/move instance: support default methods in interfaces for java 8 (IDEA-154833)

java/java-tests/testData/refactoring/convertToInstance8Method/Simple.java

@@ -0,0 +1,16 @@
+public class Y {
+    public void foo() {
+    }
+}
+public class X {
+    static void <caret>method(Y y) {
+        System.out.println(y);
+        y.foo();
+    }
+
+    {
+      Y y = new Y();
+      method(y);
+      method(new Y());
+    }
+}