Wrong plot labels in partial dependence plots

[Andy-McCarthy]

library(gbm)
Heart <- read.csv("http://www-bcf.usc.edu/~gareth/ISL/Heart.csv")
Heart <- Heart[complete.cases(Heart),]
Heart$AHD <- ifelse(Heart$AHD == "Yes",1,0)
boost_heart <- gbm(AHD ~ ., data = Heart, distribution = "bernoulli", n.trees = 10000, interaction.depth = 4)
best.iter <- gbm.perf(boost_heart, method = "OOB")
plot(boost_heart, i.var = c("Thal","ChestPain"), n.trees = best.iter)

[bgreenwell]

Potentially fixed, but needs more testing, so keeping this open for now.