[Rd] svg ignores cex.axis in R3.5.1 on macOS

[Spencer Graves]

       Plots produced using svg in R 3.5.1 under macOS 10.13.6 ignores 
cex.axis=2.  Consider the following:


 > plot(1:2, cex.axis=2)
 > svg('svg_ignores_cex.axis.svg')
 > plot(1:2, cex.axis=2)
 > dev.off()
 > sessionInfo()
R version 3.5.1 (2018-07-02)
Platform: x86_64-apple-darwin15.6.0 (64-bit)
Running under: macOS High Sierra 10.13.6

Matrix products: default
BLAS: 
/Library/Frameworks/R.framework/Versions/3.5/Resources/lib/libRblas.0.dylib
LAPACK: 
/Library/Frameworks/R.framework/Versions/3.5/Resources/lib/libRlapack.dylib

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods base

loaded via a namespace (and not attached):
[1] compiler_3.5.1


       ** The axis labels are appropriately expanded with the first 
"plot(1:2, cex.axis=2)".  However, when I wrote that to an svg file and 
opened it in other applications (GIMP and Safari), the cex.axis request 
was ignored.  This also occurred inside RStudio on my Mac. It worked 
properly using R 3.2.1 under Windows 7.


       Thanks,
       Spencer Graves