Forces small delay before showing accessible tooltip on focus  (#12849)

Screen reader (JAWS 14) seems to get confused about the focused item if
the tooltip is shown on focus. This commit forces small delay before
showing the tooltip. More info, see
http://www.w3.org/TR/2011/CR-wai-aria-20110118/roles#tooltip

Change-Id: I2973a1a3844936e09fef28afe37a0ecbdda69122