Tooltip: track + delay causes a flicker on show

[ash]

Hello,

I have discovered, I think, a bug in tooltip widget.

If I initialize tracked tooltip with delay option, in some cases the tooltip is closed and reopen when I move the mouse from outside to inside the block.

After several tests, for a mouse tracked tooltip with delay, the _open method of the widget position the tooltip before the end of the delay.

I've found an issue and you can test it to jsFiddle: ​http://jsfiddle.net/ash0/ZR4fU/5/

[Scott González]

The tooltip isn't closed and reopened, there's just a flicker because it's positioned incorrectly for the first frame. Whatever you did in an attempt to fix it in your tooltipX implementation is actually worse as the tooltip is positioned at the bottom of the document instead.

[Scott González]

This is tricky to implement properly. #8644 was an attempt at fixing this (and mostly does fix it). The problem is that when using a delay, we don't have a hook into when the delay finishes. In the provided test case, there's no animation after the delay, so using the _show() callback would work, but that won't work if there is an animation after the delay. We might need to explicitly handle the delay inside tooltip.