Fix both issues of the refresh() function: #2844 (promise called sometimes too soon) and #2812 (promise never called if no less files were declared).
Fix both issues of the refresh() function: #2844 (promise called sometimes too soon) and #2812 (promise never called if no less files were declared).

arusanov/less.js,SkReD/less.js,gencer/less.js,arusanov/less.js,seven-phases-max/less.js,less/less.js,less/less.js,gencer/less.js,foresthz/less.js,less/less.js,SkReD/less.js,seven-phases-max/less.js,foresthz/less.js