Iterate on symbols, not on scopes

- This way it is easier to get the correct results

idea/idea-completion/testData/basic/common/primitiveCompletion/classFieldsAndFunctionsFromInnerClassExplicitReceiver.kt

@@ -0,0 +1,18 @@
+class A {
+    fun aa() {}
+    val aaa = 10
+
+    inner class AA {
+        fun bb() {}
+        val bbb = 20
+
+        fun test() {
+            this.<caret>
+        }
+    }
+}
+
+// ABSENT: aa
+// ABSENT: aaa
+// EXIST: bb
+// EXIST: bbb

idea/idea-completion/testData/basic/common/primitiveCompletion/extensionPropertyAndFunctionImplicitReceiver.kt

@@ -0,0 +1,25 @@
+fun Any.anyFun() {}
+val Any.anyVal: Int get() = 10
+
+class A
+fun A.aFun() {}
+val A.aVal: Int get() = 10
+
+class B
+fun B.bFun() {}
+val B.bVal: Int get() = 10
+
+fun test(a: A) {
+    a.run {
+        <caret>
+
+        Unit
+    }
+}
+
+// EXIST: anyFun
+// EXIST: anyVal
+// EXIST: aVal
+// EXIST: aFun
+// ABSENT: bVal
+// ABSENT: bFun