Exposed visibility checking, a set of exposed visibility tests, some test fixes

Effective visibility mechanism introduced.
Local is considered as public, java protected as Kotlin protected, java package private as Kotlin private.

compiler/testData/diagnostics/tests/exposed/protectedJava.kt

@@ -0,0 +1,16 @@
+// FILE: Outer.java
+
+public abstract class Outer {
+    protected static class My {}
+    protected static class Your extends My {}
+    abstract protected Your foo(My my);
+}
+
+// FILE: OuterDerived.kt
+
+class OuterDerived: Outer() {
+    // valid, My has better visibility
+    protected class His: Outer.My()
+    // valid, My and Your have better visibility
+    override fun foo(my: Outer.My) = Outer.Your()
+}