use subdsec_micros() instead of subsec_nanos() / 1000
use subdsec_micros() instead of subsec_nanos() / 1000

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