Fir2Ir: do generate signatures for private declarations

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrDeclarationStorage.kt

@@ -821,7 +821,7 @@ class Fir2IrDeclarationStorage(
         thisReceiverOwner: IrClass? = irParent as? IrClass,
         predefinedOrigin: IrDeclarationOrigin? = null,
         isLocal: Boolean = false,
-        containingClass: ConeClassLikeLookupTag? = null,
+        containingClass: ConeClassLikeLookupTag? = (irParent as? IrClass)?.classId?.let { ConeClassLikeLookupTagImpl(it) },
     ): IrProperty = convertCatching(property) {
         val origin = property.computeIrOrigin(predefinedOrigin)
         val signature = if (isLocal) null else signatureComposer.composeSignature(property, containingClass)

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/signaturer/FirBasedSignatureComposer.kt

@@ -91,14 +91,12 @@ class FirBasedSignatureComposer(override val mangler: FirMangler) : Fir2IrSignat
                 )
             }
             is FirTypeAlias -> {
-                if (declaration.visibility == Visibilities.Private) return null
                 val classId = declaration.symbol.classId
                 IdSignature.CommonSignature(
                     classId.packageFqName.asString(), classId.relativeClassName.asString(), builder.hashId, builder.mask
                 )
             }
             is FirCallableDeclaration -> {
-                if (declaration.visibility == Visibilities.Private && !isTopLevelPrivate(declaration, containingClass)) return null
                 val containingClassId = containingClass?.classId
 
                 val classId = containingClassId ?: declaration.containingClass()?.classId