Debugger: Tooltip timing workarounds.

There's some bad interaction between the delayed hide,
the deleteLater() from CloseOnDelete, and the async
evaluation. Work around by start from scratch for each
tooltip. On the downside we have more flicker.

Change-Id: I4801368c07895b652e10fe1d173b21cef7869ed0
Reviewed-by: hjk <hjk121@nokiamail.com>