Please update with C# 7.2 usage

[fitdev]

Please update with C# 7.2 ref readonly returns.

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Document Details

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• ID: 26899b81-d6f9-534a-83ee-283dd8aae545
• Version Independent ID: 3061125d-7de4-97ef-ccb0-ee792d6f2ae1
• Content: readonly (C# Reference)
• Content Source: docs/csharp/language-reference/keywords/readonly.md
• Service: unspecified
• Product: dotnet-csharp
• GitHub Login: @BillWagner
• Microsoft Alias: wiwagn

[pkulikov]

Two more not mentioned use cases of the readonly keyword:

• readonly struct
• readonly ref struct