[Rd] Quartz graphic device can be extremely slow in some cases

[Juan Telleria Ruiz de Aguirre]

It might be related with this files:

https://github.com/wch/r-source/blob/trunk/src/library/grDevices/src/devQuartz.c

https://github.com/wch/r-source/blob/trunk/src/include/R_ext/QuartzDevice.h

Could we port some of the UNIX optimizations to previous code?

https://github.com/wch/r-source/blob/trunk/src/library/grDevices/R/unix/quartz.R