KT-1018: better handling of property visibility

compiler/testData/codegen/regressions/kt1018.kt

@@ -0,0 +1,12 @@
+public class StockMarketTableModel() {
+
+    public fun getColumnCount() : Int {
+        return COLUMN_TITLES?.size.sure()
+    }
+
+    class object {
+        private val COLUMN_TITLES : Array<Int?> = Array<Int?>(10)
+    }
+}
+
+fun box() : String = if(StockMarketTableModel().getColumnCount()==10) "OK" else "fail"

compiler/testData/codegen/super/traitproperty.jet

@@ -8,7 +8,7 @@ trait M {
 }
 
 class N() : M {
-    override var backingB : Int = 0
+    public override var backingB : Int = 0
 
     val a : Int
         get() {