Account for Layout ordering in Blazor

[pranavkm]

The server requires that clients send descriptors in sequence. Since MVC executes
Layouts in an inside-out manner, modify the client to explicitly order descriptors

Fixes #14474

[pranavkm]

No idea if this messes up a scenario, but all of the tests pass locally.

[pranavkm]

Layouts in MVC are rendered inside out, consequently any components in a Layout page that appear before RenderBody will have an out of order sequence number:

// _Layout.cshtml
<component type="Counter" />: sequence: 1

@RenderBody()
    // Index.cshtml
    <component type="Counter" />: sequence: 0

// _Layout.cshtml
<component type="Counter" />: sequence: 2

This trips the deserialization when it sees out-of-order sequence numbers.

[javiercn]

This sounds like a great fix, it is how it was supposed to work, we just thought they were in order already.

I’m glad it wasn’t an issue with the viewcontext not being properly copied.