Whitespace
Tooltip: on close and destroy only set title if empty or undefined. Fixed #8925 - Changes to title attribute are reverted on close

Fix jshint task.
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Running "jshint:all" (jshint) task
Linting ui/jquery.ui.tooltip.js ...ERROR
[L396:C21] W081: Too many var statements.
        var title = element.attr( "title" );