Record special descriptor in REFERENCE_TARGET for type alias object

If a type alias is used to reference an object (companion object) as a
qualifier, record FakeCallableDescriptorForTypeAliasObject in
REFERENCE_TARGET. This tells IDE that type alias was used in the file,
thus, if it's imported, such import isn't redundant.
REFERENCE_TARGET is used mostly by IDE and by ClassifierUsageChecker,
which we also have to update to handle qualifiers with
FakeCallableDescriptorForTypeAliasObject in REFERENCE_TARGET.

Rewrite some parts of ClassifierUsageChecker for cleaner interaction.

 #KT-21863 Fixed Target versions 1.2.40

core/descriptors/src/org/jetbrains/kotlin/resolve/DescriptorUtils.kt

@@ -22,7 +22,7 @@ import org.jetbrains.kotlin.descriptors.ClassKind.*
 import org.jetbrains.kotlin.descriptors.annotations.Annotated
 import org.jetbrains.kotlin.descriptors.annotations.AnnotationDescriptor
 import org.jetbrains.kotlin.descriptors.annotations.KotlinRetention
-import org.jetbrains.kotlin.descriptors.impl.TypeAliasConstructorDescriptor
+import org.jetbrains.kotlin.descriptors.impl.DescriptorDerivedFromTypeAlias
 import org.jetbrains.kotlin.incremental.components.LookupLocation
 import org.jetbrains.kotlin.name.ClassId
 import org.jetbrains.kotlin.name.FqName
@@ -50,7 +50,7 @@ fun ClassDescriptor.getClassObjectReferenceTarget(): ClassDescriptor = companion
 
 fun DeclarationDescriptor.getImportableDescriptor(): DeclarationDescriptor =
     when (this) {
-        is TypeAliasConstructorDescriptor -> containingDeclaration
+        is DescriptorDerivedFromTypeAlias -> typeAliasDescriptor
         is ConstructorDescriptor -> containingDeclaration
         is PropertyAccessorDescriptor -> correspondingProperty
         else -> this
@@ -97,13 +97,12 @@ val ClassifierDescriptorWithTypeParameters.hasCompanionObject: Boolean
 
 val ClassDescriptor.hasClassValueDescriptor: Boolean get() = classValueDescriptor != null
 
-val ClassifierDescriptorWithTypeParameters.classValueDescriptor: ClassDescriptor?
-    get() = denotedClassDescriptor?.let {
-        if (it.kind.isSingleton)
-            it
+val ClassDescriptor.classValueDescriptor: ClassDescriptor?
+    get() =
+        if (kind.isSingleton)
+            this
         else
-            it.companionObjectDescriptor
-    }
+            companionObjectDescriptor
 
 val ClassifierDescriptorWithTypeParameters.classValueTypeDescriptor: ClassDescriptor?
     get() = denotedClassDescriptor?.let {