Always add tooltip event handlers for Window (#11448)

This is needed to ensure tooltips are closed when moving the mouse
outside the component but still inside the window. In 7.1, this should
instead be implemented by overriding hasTooltip() to return true.

Merge: manual
Change-Id: I48d47474a4e4f0303fd85552612f6960fcdce0a7
Merge commit '34e6c60a5a746c0306c3a84ae8d6c21dfd84d878' into 7.1

#11448 is fixed in a different way for 7.1 because the tooltip event
handling has been slightly refactored.

Change-Id: I50db48ffdce22cdf6598daafcb022fc43ed11cf4