[macOS] macOS desktop should enable wide gamut when running with Impeller #164557
Description
From a cursory look at the code, all that needs to change is FlutterSurface.mm:
pixelFormat = kCVPixelFormatType_40ARGBLEWideGamut;
bytesPerElement = 8;
and the texture format change to MTLPixelFormatBGRA10_XR
On macOS I think detecting support is trickier, but we can use it as long as the device is apple series 3 or higher.
FYI @knopp