FIR: introduce symbolProvider.getNestedClassifierScope to choose lazy/non-lazy

For some reason this breaks two old FE based tests with member type aliases.
It's not very interesting because member aliases aren't supported.

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/JavaSymbolProvider.kt

@@ -30,6 +30,7 @@ import org.jetbrains.kotlin.fir.resolve.*
 import org.jetbrains.kotlin.fir.scopes.FirScope
 import org.jetbrains.kotlin.fir.scopes.impl.FirSuperTypeScope
 import org.jetbrains.kotlin.fir.scopes.impl.declaredMemberScope
+import org.jetbrains.kotlin.fir.scopes.impl.nestedClassifierScope
 import org.jetbrains.kotlin.fir.symbols.CallableId
 import org.jetbrains.kotlin.fir.symbols.impl.*
 import org.jetbrains.kotlin.fir.toFirSourceElement
@@ -64,6 +65,21 @@ class JavaSymbolProvider(
     override fun getTopLevelCallableSymbols(packageFqName: FqName, name: Name): List<FirCallableSymbol<*>> =
         emptyList()
 
+    override fun getNestedClassifierScope(classId: ClassId): FirScope? {
+        val symbol = this.getClassLikeSymbolByFqName(classId) ?: return null
+        val regularClass = symbol.fir
+        return if (regularClass is FirJavaClass) {
+            nestedClassifierScope(
+                classId,
+                session,
+                existingNames = regularClass.existingNestedClassifierNames,
+                symbolProvider = this
+            )
+        } else {
+            nestedClassifierScope(regularClass)
+        }
+    }
+
     override fun getClassUseSiteMemberScope(
         classId: ClassId,
         useSiteSession: FirSession,

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/deserialization/KotlinDeserializedJvmSymbolsProvider.kt

@@ -29,6 +29,7 @@ import org.jetbrains.kotlin.fir.references.impl.FirErrorNamedReferenceImpl
 import org.jetbrains.kotlin.fir.references.impl.FirResolvedNamedReferenceImpl
 import org.jetbrains.kotlin.fir.resolve.*
 import org.jetbrains.kotlin.fir.scopes.FirScope
+import org.jetbrains.kotlin.fir.scopes.impl.nestedClassifierScope
 import org.jetbrains.kotlin.fir.symbols.impl.*
 import org.jetbrains.kotlin.fir.types.FirResolvedTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirErrorTypeRefImpl
@@ -392,6 +393,12 @@ class KotlinDeserializedJvmSymbolsProvider(
         }
     }
 
+    override fun getNestedClassifierScope(classId: ClassId): FirScope? {
+        return findRegularClass(classId)?.let {
+            nestedClassifierScope(it)
+        }
+    }
+
     private fun getPackageParts(packageFqName: FqName): Collection<PackagePartsCacheData> {
         return packagePartsCache.getOrPut(packageFqName) {
             try {