Add actual: handle already existing declarations more precisely

#KT-23693 Fixed

idea/testData/multiModuleQuickFix/classFunctionSameSignature/jvm/jvm.kt

@@ -0,0 +1,8 @@
+// "Add missing actual members" "true"
+// DISABLE-ERRORS
+
+actual object <caret>O {
+    fun <T> hello(): MutableMap<String, T> {
+        TODO("not implemented")
+    }
+}