Initial implementation of KT-8209 Support static member completion without writing the class name

idea/idea-completion/testData/basic/multifile/ObjectMembers/ObjectMembers.dependency.kt

@@ -0,0 +1,19 @@
+package test
+
+object KotlinObject {
+    fun funFromObject() { }
+    private fun privateFun(){}
+}
+
+class KotlinClass {
+    companion object SomeName {
+        fun funFromCompanionObject() { }
+        private fun privateFun(){}
+    }
+}
+
+class AnotherKotlinClass {
+    private companion object {
+        fun funFromPrivateCompanionObject() { }
+    }
+}

idea/idea-completion/testData/basic/multifile/ObjectMembers/ObjectMembers.kt

@@ -0,0 +1,11 @@
+package first
+
+fun testFun() {
+    funFromO<caret>
+}
+
+// INVOCATION_COUNT: 2
+// EXIST: { allLookupStrings: "funFromObject", itemText: "KotlinObject.funFromObject", tailText: "() (test)", typeText: "Unit", attributes: "" }
+// EXIST: { allLookupStrings: "funFromCompanionObject", itemText: "KotlinClass.funFromCompanionObject", tailText: "() (test)", typeText: "Unit", attributes: "" }
+// ABSENT: privateFun
+// ABSENT: funFromPrivateCompanionObject