Metal: Fix robust initialization of PVRTC1 textures Replace Region Validation: rowBytes must be 0 for: * MTLPixelFormatPVRTC_RGB_2BPP * MTLPixelFormatPVRTC_RGB_2BPP_sRGB * MTLPixelFormatPVRTC_RGB_4BPP * MTLPixelFormatPVRTC_RGB_4BPP_sRGB * MTLPixelFormatPVRTC_RGBA_2BPP * MTLPixelFormatPVRTC_RGBA_2BPP_sRGB * MTLPixelFormatPVRTC_RGBA_4BPP * MTLPixelFormatPVRTC_RGBA_4BPP_sRGB Fixed: angleproject:8370 Change-Id: I153bea5bb487f79b0966be0b8670a2ee4e3aeb39 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4915704 Reviewed-by: Kenneth Russell <kbr@chromium.org> Commit-Queue: Alexey Knyazev <lexa.knyazev@gmail.com>