Revert "Revert "Revert "Qt Designer: Temporarily disable loading of QDeclarativeView plugin."

Re-enable the QDeclarativeView plugin.

This reverts commit a60aa90f5ca00e32a1271a476f5da650dddebfda.

Task-number: QTCREATORBUG-10273
Task-number: QTCREATORBUG-13616
Task-number: QTBUG-35006
Change-Id: Id8c34e040508f7509501533eceaa75613a46baa8
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>