[FIR] Use proper scope lookup for classifiers

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/mpp/FirExpectActualMatchingContext.kt

@@ -8,7 +8,6 @@ package org.jetbrains.kotlin.fir.resolve.transformers.mpp
 import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibility
-import org.jetbrains.kotlin.descriptors.isEnumClass
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.isSubstitutionOrIntersectionOverride
@@ -27,7 +26,6 @@ import org.jetbrains.kotlin.types.AbstractTypeChecker
 import org.jetbrains.kotlin.types.TypeCheckerState
 import org.jetbrains.kotlin.types.Variance
 import org.jetbrains.kotlin.types.model.*
-import org.jetbrains.kotlin.utils.addIfNotNull
 import org.jetbrains.kotlin.utils.addToStdlib.UnsafeCastFunction
 import org.jetbrains.kotlin.utils.addToStdlib.castAll
 
@@ -170,9 +168,13 @@ class FirExpectActualMatchingContext(
                 scope.getMembersTo(this, name)
             }
 
-            // TODO: replace with scope lookup
-            for (name in symbol.declarationSymbols.mapNotNull { (it as? FirRegularClassSymbol)?.classId?.shortClassName }) {
-                addIfNotNull(scope.getSingleClassifier(name) as? FirRegularClassSymbol)
+            for (name in scope.getClassifierNames()) {
+                scope.processClassifiersByName(name) {
+                    // We should skip nested classes from supertypes here
+                    if (it is FirRegularClassSymbol && it.classId.parentClassId == symbol.classId) {
+                        add(it)
+                    }
+                }
             }
             getConstructorsTo(this, scope)
         }