Auto merge of #3654 - matthiaskrgr:rustup, r=phansch
Auto merge of #3654 - matthiaskrgr:rustup, r=phansch

rustup: the features if_while_or_patterns has been stabilized

aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust,aidancully/rust