[Impeller] Metal validation failures on CanRenderTiledTexture/Metal. #109648
Description
The following validation error is reported.
[ RUN ] Play/AiksTest.CanRenderTiledTexture/Metal
-[MTLDebugBlitCommandEncoder generateMipmapsForTexture:]:1109:
failed assertion
`Generate Mipmaps For Texture Validation [tex mipmapLevelCount](1) must be > 1.'
The steps to enable Metal validation in command line apps (like the Google Test harness) are here.