Correct completion of nested/inner classes after dot

#KT-1889 Fixed

idea/testData/completion/smart/InnerClass.kt

@@ -0,0 +1,18 @@
+trait T
+
+class C {
+    inner class Inner1(s: String) : T
+    inner class Inner2 : T
+    inner class Inner3
+    class Nested: T
+}
+
+fun foo(c: C): T {
+    return c.<caret>
+}
+
+// EXIST: { lookupString: "Inner1", itemText: "Inner1", tailText: "(s: String)", typeText: "C.Inner1" }
+// EXIST: { lookupString: "Inner2", itemText: "Inner2", tailText: "()", typeText: "C.Inner2" }
+// ABSENT: Inner3
+// ABSENT: Nested
+// NUMBER: 2