Offer to make INVISIBLE_MEMBER protected if referenced from subclass

So #KT-19614 Fixed

idea/testData/quickfix/increaseVisibility/invisibleFake/methodToProtected2.kt

@@ -0,0 +1,14 @@
+// "Make 'doSth' protected" "true"
+
+open class A {
+    private fun doSth() {
+    }
+}
+
+open class B : A()
+
+class C : B() {
+    fun bar() {
+        <caret>doSth()
+    }
+}