[XC] Fallback to reflection-based bindings for bindings with "invalid" path

[simonrozsival]

Description of Change

We've improved binding optimizations in .NET 9 and it is now possible to compile all sorts of bindings that weren't supported in .NET 8 and earlier. This change can break existing code though:

• In the cases when there is a binding with a Source but it inherits the x:DataType from the parent, there can often be a mismatch between the x:DataType and the type of the Source
• Sometimes customers want to reference another element and access its BindingContext ({Binding BindingContext.Title Source={x:Reference ...}}). Since we don't support casting in the path, XamlC won't be able to correctly resolve and build the property chain (in the example BindingContext is of type object and it doesn't have any property Title).

While there are workarounds to these issues, it might be better to just fallback to a reflection-based binding that will resolve the actual properties at runtime in these cases to keep the apps working and produce a warning so that the developer can either choose to ignore it or address it. Feedback is very welcome.

I recommend hiding whitespace changes when looking at the code diff.

Issues Fixed

Fixes #23711

[rmarinho]

/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/AutomationProperties.xaml(9,4): XamlC warning XC0618: Property, Property setter or BindableProperty "Name" is deprecated. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/AutomationProperties.xaml(10,4): XamlC warning XC0618: Property, Property setter or BindableProperty "HelpText" is deprecated. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/AutomationProperties.xaml(12,4): XamlC warning XC0618: Property, Property setter or BindableProperty "LabeledBy" is deprecated. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Issues/Maui17484.xaml(10,17): XamlC warning XC0618: Property, Property setter or BindableProperty "Name" is deprecated. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/WarnOnObsolete.xaml(6,25): XamlC warning XC0618: Property, Property setter or BindableProperty "ObsoleteBP" is deprecated. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/WarnOnObsolete.xaml(6,42): XamlC warning XC0618: Property, Property setter or BindableProperty "ObsoleteProp" is deprecated. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/WarnOnObsolete.xaml(6,61): XamlC warning XC0618: Property, Property setter or BindableProperty "ObsoletePropSetter" is deprecated. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/BindingsCompiler.xaml(28,20): XamlC error XC0045: Binding: Property "GlobalText" not found on "System.Object". [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/BindingsCompiler.xaml : XamlC error : Index (zero based) must be greater than or equal to zero and less than the size of the argument list. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Issues/Gh2517.xaml(6,12): XamlC error XC0045: Binding: Property "MissingProperty" not found on "Microsoft.Maui.Controls.Label". [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Issues/Gh2517.xaml : XamlC error : Index (zero based) must be greater than or equal to zero and less than the size of the argument list. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Issues/Gh3606.xaml(4,16): XamlC error XC0045: Binding: Property "Content" not found on "System.String". [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Issues/Gh3606.xaml : XamlC error : Index (zero based) must be greater than or equal to zero and less than the size of the argument list. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Issues/Maui20768.xaml(6,32): XamlC error XC0045: Binding: Property "Title" not found on "Microsoft.Maui.Controls.Xaml.UnitTests.ViewModel20768". [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Issues/Maui20768.xaml : XamlC error : Index (zero based) must be greater than or equal to zero and less than the size of the argument list. [/Users/builder/azdo/_work/2/s/src/Controls/tests/Xaml.UnitTests/Controls.Xaml.UnitTests.csproj]
    7 Warning(s)
    8 Error(s)

[rmarinho]

/rebase

Errors have been fixed