NativeCapture returns a solid color image

[ryantrem]

Describe the bug
NativeCapture has regressed and the rbga8 buffer we get back is now just a solid color. It is not the same solid color each frame though, it seems to alternate between gray and the default clear color.

To Reproduce
Steps to reproduce the behavior:
I tested this in Babylon React Native, so I haven't confirmed it repros in Babylon Native directly but I expect it does.
In that context, create a CaptureSession and dump the frame data to a bitmap to see the solid color. I can create a repro branch later also, but getting this issue logged now.

Expected behavior
Captured frame has the actual frame data in the rgba byte buffer.

Other
Android and iOS