[quartz] Set GdkQuartzView wantsLayer.
Apparently wantsUpdateLayer by itself isn't sufficient. Also #ifdef wantsUpdateLayer for macOS X 10.8 and later; earlier versions don't provide it.
Fixes #5393 (closed)
Apparently wantsUpdateLayer by itself isn't sufficient. Also #ifdef wantsUpdateLayer for macOS X 10.8 and later; earlier versions don't provide it.
Fixes #5393 (closed)