QCompleter does not function correctly when within a QGraphicsView

When a QCompleter is added to a QLineEdit, which is then added to a QGraphicsScene, the QCompleter does not function as it does when within a normal Widget. The completer dialog seems to popup as designed under Windows (Linux seems to have parenting issues), but the dialog only appears on odd quantities of key presses. When the count of key presses is even, the dialog box disappears, which seems to imply a focus issue.

Example, when completing the word "One".

Type "O", dialog appears. Type "n", the dialog disappears". Type "e", the dialog reappears.

Attachment is working example of this bug.

Tested in 4.6.3 and 4.7.0-RC1 and experienced same behavior.