Follow-up to #13907: simplify JS logic for focus shim
Merge pull request #14160 from hnrch02/simplify-button-focus-logic

Follow-up to #13907: simplify JS logic for focus shim
speed up js tests a bit
Tabs to spaces
Merge pull request #14171 from wangsai/tab2space

Tabs to spaces in variables.less
Merge pull request #14055 from twbs/fat-speed-up-tests

speed up js tests a bit