Stripe width of stripe width large enough to contain stripe labels in ggplot

Any ideas (elegant preferred, but brute force other than just making the patch area wider are also welcome) for making the label strips wide enough to hold the long label without wrapping the labels in the following example? I don't see any parameters in element_text

or facet_wrap

for this ...

library(ggplot2)
dd <- expand.grid(x=1:3,
      f=c("lab","longer label","very very very long label"))
ggplot(dd,aes(x,x))+geom_point()+facet_wrap(~f)
ggsave("strips.png",height=3,width=3)