Use correct shape when there is a single child
Use correct shape when there is a single child

graydon/rust,aidancully/rust,graydon/rust,SingingTree/rustfmt,aidancully/rust,aidancully/rust,aidancully/rust,rust-lang/rustfmt,SingingTree/rustfmt,graydon/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,rust-lang/rustfmt,aidancully/rust