Fixed smart completion of functions with "::"

#KT-6073 Fixed

idea/testData/completion/smart/FunctionReference10.kt

@@ -0,0 +1,19 @@
+class C {
+    fun foo(s: String): Boolean = true
+
+    fun bar() {
+        listOf("a").filter(<caret>)
+    }
+
+    class object {
+        fun staticFoo(s: String): Boolean = true
+    }
+}
+
+fun C.extensionFoo(s: String): Boolean = true
+fun globalFoo(s: String): Boolean = true
+
+// ABSENT: ::foo
+// ABSENT: ::staticFoo
+// ABSENT: ::extensionFoo
+// EXIST: ::globalFoo

idea/testData/completion/smart/FunctionReference11.kt

@@ -0,0 +1,19 @@
+import kotlin.platform.platformName
+
+class C(i: Int){
+    class Nested
+    inner class Inner
+
+    fun bar() {
+        foo(<caret>)
+    }
+}
+
+platformName("foo1")
+fun foo(p: () -> C.Nested){}
+
+platformName("foo2")
+fun foo(p: () -> C.Inner){}
+
+// EXIST: ::Nested
+// ABSENT: ::Inner

idea/testData/completion/smart/FunctionReference12.kt

@@ -0,0 +1,13 @@
+class C {
+    fun foo(p: C.() -> Unit){}
+
+    fun bar() {
+        foo(<caret>)
+    }
+
+    fun f1(){}
+    fun C.f2(){}
+}
+
+// EXIST: ::f1
+// ABSENT: ::f2

idea/testData/completion/smart/FunctionReference8.kt.todo

@@ -7,5 +7,5 @@ fun bar() {
 fun String.f1(){}
 fun f2(){}
 
-// EXIST: ::f1
+// EXIST: String::f1
 // ABSENT: ::f2