Rollup merge of #35452 - ubsan:precedence, r=steveklabnik
Rollup merge of #35452 - ubsan:precedence, r=steveklabnik

Finish fixing the operator precedence tables

Add the unstable `:` colon and `<-` inplace operators.

r? @steveklabnik

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