Can't scaffold SQL Server index with fill factor in EF Core 6 preview 4

[ErikEJ]

System.Exception: Reverse engineer error: 
System.InvalidCastException: Unable to cast object of type 'System.Byte' to type 'System.Nullable`1[System.Int32]'.
   at int? Microsoft.EntityFrameworkCore.SqlServerIndexExtensions.GetFillFactor(IReadOnlyIndex index)
   at IEnumerable<IAnnotation> Microsoft.EntityFrameworkCore.SqlServer.Metadata.Internal.SqlServerAnnotationProvider.For(ITableIndex index)+MoveNext()
   at void Microsoft.EntityFrameworkCore.Infrastructure.AnnotatableBase.AddAnnotations(AnnotatableBase annotatable, IEnumerable<IAnnotation> annotations) x 2
   at IRelationalModel Microsoft.EntityFrameworkCore.Metadata.Internal.RelationalModel.Create(IModel model, IRelationalAnnotationProvider relationalAnnotationProvider)
   at IModel Microsoft.EntityFrameworkCore.Metadata.Internal.RelationalModel.Add(IModel model, IRelationalAnnotationProvider relationalAnnotationProvider)
   at void Microsoft.EntityFrameworkCore.Infrastructure.RelationalModelRuntimeInitializer.InitializeModel(IModel model, bool preValidation)
   at IModel Microsoft.EntityFrameworkCore.Infrastructure.ModelRuntimeInitializer.Initialize(IModel model, bool designTime, IDiagnosticsLogger<Validation> validationLogger)+((ModelRuntimeInitializer, IModel model, bool designTime, IDiagnosticsLogger<Validation> validationLogger) args) => { } [0]
   at Annotation Microsoft.EntityFrameworkCore.Infrastructure.AnnotatableBase+<>c__30<TValue, TArg>.<GetOrAddRuntimeAnnotationValue>b__30_0(?)+(string n, (Func<TArg, TValue> CreateValue, TArg Argument, AnnotatableBase Annotatable) t) => { }
   at TValue System.Collections.Concurrent.ConcurrentDictionary<TKey, TValue>.GetOrAdd<TArg>(TKey key, Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument)
   at TValue Microsoft.EntityFrameworkCore.Infrastructure.AnnotatableBase.GetOrAddRuntimeAnnotationValue<TValue, TArg>(string name, Func<TArg, TValue> valueFactory, TArg factoryArgument)
   at IModel Microsoft.EntityFrameworkCore.Infrastructure.ModelRuntimeInitializer.Initialize(IModel model, bool designTime, IDiagnosticsLogger<Validation> validationLogger)
   at IModel Microsoft.EntityFrameworkCore.Scaffolding.Internal.RelationalScaffoldingModelFactory.Create(DatabaseModel databaseModel, ModelReverseEngineerOptions options)
   at ScaffoldedModel RevEng.Core.ReverseEngineerScaffolder.ScaffoldModel(string connectionString, DatabaseModelFactoryOptions databaseOptions, ModelReverseEngineerOptions modelOptions, ModelCodeGenerationOptions codeOptions, bool removeNullableBoolDefaults, bool excludeNavigations, bool dbContextOnly, bool entitiesOnly, bool useSchemaFolders, ServiceProvider serviceProvider) in C:/Code/EFCorePowerTools/src/GUI/RevEng.Core/ReverseEngineerScaffolder.cs:line 212
   at SavedModelFiles RevEng.Core.ReverseEngineerScaffolder.GenerateDbContext(ReverseEngineerCommandOptions options, ServiceProvider serviceProvider, List<string> schemas, string outputContextDir, string modelNamespace, string contextNamespace) in C:/Code/EFCorePowerTools/src/GUI/RevEng.Core/ReverseEngineerScaffolder.cs:line 58
   at ReverseEngineerResult RevEng.Core.ReverseEngineerRunner.GenerateFiles(ReverseEngineerCommandOptions options) in C:/Code/EFCorePowerTools/src/GUI/RevEng.Core/ReverseEngineerRunner.cs:line 86
   at int efreveng.Program.Main(string[] args) in C:/Code/EFCorePowerTools/src/GUI/efreveng/Program.cs:line 58

    at  EFCorePowerTools.Handlers.ReverseEngineer.ResultDeserializer.BuildResult (EFCorePowerTools, Version=2.5.665.0, Culture=neutral, PublicKeyToken=d9645e6262c2eca7)
    at  EFCorePowerTools.Handlers.ReverseEngineer.EfRevEngLauncher+<GetOutputAsync>d__9.MoveNext (EFCorePowerTools, Version=2.5.665.0, Culture=neutral, PublicKeyToken=d9645e6262c2eca7)
    at  System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)
    at  System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)
    at  System.Runtime.CompilerServices.TaskAwaiter`1.GetResult (mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)
    at  EFCorePowerTools.Handlers.ReverseEngineer.EfRevEngLauncher+<LaunchExternalRunnerAsync>d__5.MoveNext (EFCorePowerTools, Version=2.5.665.0, Culture=neutral, PublicKeyToken=d9645e6262c2eca7)
    at  System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)
    at  System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)
    at  System.Runtime.CompilerServices.TaskAwaiter`1.GetResult (mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)
    at  EFCorePowerTools.Handlers.ReverseEngineer.ReverseEngineerHandler+<GenerateFilesAsync>d__13.MoveNext (EFCorePowerTools, Version=2.5.665.0, Culture=neutral, PublicKeyToken=d9645e6262c2eca7)
    at  System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)
    at  System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)
    at  System.Runtime.CompilerServices.TaskAwaiter.GetResult (mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089)
    at  EFCorePowerTools.Handlers.ReverseEngineer.ReverseEngineerHandler+<ReverseEngineerCodeFirstAsync>d__6.MoveNext (EFCorePowerTools, Version=2.5.665.0, Culture=neutral, PublicKeyToken=d9645e6262c2eca7)

Include provider and version information

EF Core version: 6.0 preview 4
Database provider: (e.g. Microsoft.EntityFrameworkCore.SqlServer)
Target framework: .NET 5.0

[roji]

This seems like a bug was was present in the original PR: the metadata APIs for index fill factor use int, but SqlServerDatabaseModelFactory produces a byte. However, before preview4 we didn't use the metadata APIs during scaffolding, so the issue didn't manifest.

(note also that in 5.0.6 we also scaffold .HasFillFactor((byte)80) with the useless cast because of this)

We could change the metadata APIs to accept a byte (which is what SQL Server's sys.indexes exposes), but at this point it's probably simpler (and less breaking) to just have SqlServerDatabaseModelFactory produce an int. We already have metadata validation in place that the value is between 0 and 100.