FIR deserializer: add proper container class id to nested class members

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/deserialization/ClassDeserialization.kt

@@ -44,10 +44,14 @@ fun deserializeClassToSymbol(
     ).apply {
 
         val context =
-            parentContext?.childContext(classProto.typeParameterList, nameResolver, TypeTable(classProto.typeTable))
-                ?: FirDeserializationContext.createForClass(
-                    classId, classProto, nameResolver, session, FirBuiltinAnnotationDeserializer(session, nameResolver)
-                )
+            parentContext?.childContext(
+                classProto.typeParameterList,
+                nameResolver,
+                TypeTable(classProto.typeTable),
+                classId.relativeClassName
+            ) ?: FirDeserializationContext.createForClass(
+                classId, classProto, nameResolver, session, FirBuiltinAnnotationDeserializer(session, nameResolver)
+            )
         typeParameters += context.typeDeserializer.ownTypeParameters.map { it.firUnsafe() }
         annotations += context.annotationDeserializer.loadClassAnnotations(classProto)
 

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/deserialization/FirMemberDeserializer.kt

@@ -43,7 +43,8 @@ class FirDeserializationContext(
     fun childContext(
         typeParameterProtos: List<ProtoBuf.TypeParameter>,
         nameResolver: NameResolver = this.nameResolver,
-        typeTable: TypeTable = this.typeTable
+        typeTable: TypeTable = this.typeTable,
+        relativeClassName: FqName? = this.relativeClassName
     ): FirDeserializationContext = FirDeserializationContext(
         nameResolver, typeTable, versionRequirementTable, session, packageFqName, relativeClassName,
         FirTypeDeserializer(

compiler/fir/resolve/testData/resolve/stdlib/companionLoad.kt

@@ -0,0 +1,3 @@
+fun main() {
+    val y = Int.MAX_VALUE
+}

compiler/fir/resolve/testData/resolve/stdlib/companionLoad.txt

@@ -0,0 +1,4 @@
+FILE: companionLoad.kt
+    public final fun main(): R|kotlin/Unit| {
+        lval y: R|kotlin/Int| = R|kotlin/Int|.R|kotlin/Int.Companion.MAX_VALUE|
+    }

compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirResolveTestCaseWithStdlibGenerated.java

@@ -34,6 +34,11 @@ public class FirResolveTestCaseWithStdlibGenerated extends AbstractFirResolveTes
         runTest("compiler/fir/resolve/testData/resolve/stdlib/arrayFirstOrNull.kt");
     }
 
+    @TestMetadata("companionLoad.kt")
+    public void testCompanionLoad() throws Exception {
+        runTest("compiler/fir/resolve/testData/resolve/stdlib/companionLoad.kt");
+    }
+
     @TestMetadata("components.kt")
     public void testComponents() throws Exception {
         runTest("compiler/fir/resolve/testData/resolve/stdlib/components.kt");