[HybridWebView] Support calling void and "no return" functions in JS

[mattleibow]

Description of Change

Currently, the HybridWebView assumes that all functions return a value and immediately tries to deserialize the result.

This PR changes that to first check to see if the value is "null" / "undefined" and then skips the deserialization since those values represent null in .NET.

There is also a new API in the HybridWebView control that provides a way to avoid having to provide a type and type info that will just be ignored.

After this PR, there will be 3 ways to invoke a void function:

1. hybridWebView.InvokeJavaScriptAsync<TReturn>(name, TReturn info, ...)
   This is the current way, we just no longer crash if the return value is null.
2. hybridWebView.InvokeJavaScriptAsync<TReturn>(name, null, ...)
   This is a better way, we allow passing null as the type info, but we still need the generic argument - which can be anything, object, string, etc
3. NEW hybridWebView.InvokeJavaScriptAsync(name, ...)
   This is the new API where it is not generic and does not have a return type info parameter

Issues Fixed

Fixes #26766

Outstanding Work

Since the API can't be changed for .NET 9, we will need to delay the one small part: #27191

Void methods can still be run, just not with the new API.

[Copilot]

Copilot reviewed 4 out of 20 changed files in this pull request and generated 2 comments.

Files not reviewed (16)

• src/Controls/src/Core/PublicAPI/net-android/PublicAPI.Unshipped.txt: Language not supported
• src/Controls/src/Core/PublicAPI/net-ios/PublicAPI.Unshipped.txt: Language not supported
• src/Controls/src/Core/PublicAPI/net-maccatalyst/PublicAPI.Unshipped.txt: Language not supported
• src/Controls/src/Core/PublicAPI/net-tizen/PublicAPI.Unshipped.txt: Language not supported
• src/Controls/src/Core/PublicAPI/net-windows/PublicAPI.Unshipped.txt: Language not supported
• src/Controls/src/Core/PublicAPI/net/PublicAPI.Unshipped.txt: Language not supported
• src/Controls/src/Core/PublicAPI/netstandard/PublicAPI.Unshipped.txt: Language not supported
• src/Controls/tests/DeviceTests/Resources/Raw/HybridTestRoot/index.html: Language not supported
• src/Core/src/PublicAPI/net-android/PublicAPI.Unshipped.txt: Language not supported
• src/Core/src/PublicAPI/net-ios/PublicAPI.Unshipped.txt: Language not supported
• src/Core/src/PublicAPI/net-maccatalyst/PublicAPI.Unshipped.txt: Language not supported
• src/Core/src/PublicAPI/net-tizen/PublicAPI.Unshipped.txt: Language not supported
• src/Core/src/PublicAPI/net-windows/PublicAPI.Unshipped.txt: Language not supported
• src/Core/src/PublicAPI/net/PublicAPI.Unshipped.txt: Language not supported
• src/Core/src/PublicAPI/netstandard/PublicAPI.Unshipped.txt: Language not supported
• src/Core/src/PublicAPI/netstandard2.0/PublicAPI.Unshipped.txt: Language not supported

Comments suppressed due to low confidence (1)

src/Controls/src/Core/HybridWebView/HybridWebView.cs:84

• Ensure that the new method InvokeJavaScriptAsync in HybridWebView is covered by tests.

public async Task InvokeJavaScriptAsync(string methodName, object?[]? paramValues = null, JsonTypeInfo?[]? paramJsonTypeInfos = null)