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

This reverts commit f7f37e7fa2d98f777cc7b6035bb6ff924c75e1fa.

The crash reocurred, disable the QDeclarativeView plugin again.

Task-number: QTCREATORBUG-10273
Task-number: QTBUG-35006

Change-Id: I20406066e0752c6410223ca34abecda8d9b020f6
Reviewed-by: Eike Ziller <eike.ziller@digia.com>