CopyBuffer() method of SoftwareBitmap to an array crashes when trimming is enabled

[lhak]

Describe the bug

When using the CopyBuffer() method of a SoftwareBitmap to copy the pixels to a byte array the app crashes with an "Invalid cast" exception if trimming is enabled

To Reproduce

1. Run attached repro project

SoftwareBitmapTrimRepro.zip

Expected behavior

Should work the same as without trimming enabled

Version Info

WindowsAppSDK 1.2

Additional context

[lhak]

It seems that the issue is caused by the WindowsRuntimeBuffer class (and related extension methods like AsBuffer() for arrays) when trimming is enabled. Workaround: Add a TrimmerRootDescriptor file with the following content:

<linker>
  <assembly fullname="Microsoft.Windows.SDK.NET">
    <type fullname="System.Runtime.InteropServices.WindowsRuntime.WindowsRuntimeBuffer"/>
  </assembly>
</linker>