Fix the position of the hovercard

The desired position was 'right', but it appeared 'bottom-right',
because the height of the hovercard was calculated as 2px at the time
of updating the position.

Debugging the problem I have checked that several dom-ifs were not yet
evaluated properly, so a flush() before updating the hovercard position
fixes the problem.

Bug: Issue 13080
Change-Id: Id0d98b68799d80fce3dd861dafa1ce32158e62b5
(cherry picked from commit b8a2b306f1b7070e7b31b29259dd7bdfef145780)