JSFiddle - React, Tailwind, and code Playground
JavaScript
//http://codegolf.stackexchange.com/questions/12525/javascript-smallest-code-to-convert-seconds-to-time
function x(T,Z,M){return s=T%60|0,m=T/60%60|0,h=T/3600|0,(Z&&!h?'':h+'hrs. ')+(Z&&!m?'':m+'min. ')+(M||Z&&!s?'':s+'sec.')}
console.log(("function(T,Z,M){return s=T%60|0,m=T/60%60|0,h=T/3600|0,(Z&&!h?'':h+'hrs. ')+(Z&&!m?'':m+'min. ')+(M||Z&&!s?'':s+'sec.')}").length);
console.log('x:',x(3600))
console.log('x:',x(3600,true))
console.log('x:',x(3600,false,true))