FIR: fix incorrect handling of suspend function typealiases again

The previous attempt stopped this code from throwing an exception during
serialization, but the arity is still wrong so an exception is now throw
when reading the serialized type.

^KT-50997 Fixed

compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBlackBoxCodegenTestGenerated.java

@@ -49409,6 +49409,12 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
             runTest("compiler/testData/codegen/box/typealias/genericTypeAliasConstructor2.kt");
         }
 
+        @Test
+        @TestMetadata("incorrectTypeOfTypealiasForSuspendFTMM.kt")
+        public void testIncorrectTypeOfTypealiasForSuspendFTMM() throws Exception {
+            runTest("compiler/testData/codegen/box/typealias/incorrectTypeOfTypealiasForSuspendFTMM.kt");
+        }
+
         @Test
         @TestMetadata("incorrectTypeOfTypealiasForSuspendFunctionalType.kt")
         public void testIncorrectTypeOfTypealiasForSuspendFunctionalType() throws Exception {

compiler/fir/providers/src/org/jetbrains/kotlin/fir/types/InferenceUtils.kt

@@ -112,9 +112,9 @@ fun ConeKotlinType.suspendFunctionTypeToFunctionTypeWithContinuation(session: Fi
     val kind =
         if (isKFunctionType(session)) FunctionClassKind.KFunction
         else FunctionClassKind.Function
-    val functionalTypeId = ClassId(kind.packageFqName, kind.numberedClassName(typeArguments.size))
     val fullyExpandedType = type.fullyExpandedType(session)
     val typeArguments = fullyExpandedType.typeArguments
+    val functionalTypeId = ClassId(kind.packageFqName, kind.numberedClassName(typeArguments.size))
     val lastTypeArgument = typeArguments.last()
     return ConeClassLikeTypeImpl(
         ConeClassLikeLookupTagImpl(functionalTypeId),