Don't report "Redundant Companion reference" on accessing nested object

So #KT-23620 Fixed

idea/src/org/jetbrains/kotlin/idea/inspections/RedundantCompanionReferenceInspection.kt

@@ -16,6 +16,7 @@ import org.jetbrains.kotlin.idea.caches.resolve.resolveToCall
 import org.jetbrains.kotlin.idea.references.mainReference
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
+import org.jetbrains.kotlin.resolve.calls.util.FakeCallableDescriptorForObject
 
 class RedundantCompanionReferenceInspection : AbstractKotlinInspection() {
     override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean): PsiElementVisitor {
@@ -31,7 +32,7 @@ class RedundantCompanionReferenceInspection : AbstractKotlinInspection() {
             val grandParent = parent.parent as? KtQualifiedExpression
             if (grandParent != null) {
                 val grandParentDescriptor = grandParent.resolveToCall()?.resultingDescriptor ?: return
-                if (grandParentDescriptor is ConstructorDescriptor) return
+                if (grandParentDescriptor is ConstructorDescriptor || grandParentDescriptor is FakeCallableDescriptorForObject) return
             }
 
             holder.registerProblem(

idea/testData/inspectionsLocal/redundantCompanionReference/companionNestedObject.kt

@@ -0,0 +1,9 @@
+// PROBLEM: none
+
+class Owner {
+    companion object {
+        object InCompanion
+    }
+}
+
+val y = Owner.<caret>Companion.InCompanion

idea/tests/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java

@@ -2805,6 +2805,12 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
             doTest(fileName);
         }
 
+        @TestMetadata("companionNestedObject.kt")
+        public void testCompanionNestedObject() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/redundantCompanionReference/companionNestedObject.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("directCompanion.kt")
         public void testDirectCompanion() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/inspectionsLocal/redundantCompanionReference/directCompanion.kt");