QmlDesigner.Instances: Changing qDebug to qWarning

A crash of the puppet is kind of expected and we should use
qWarning. Showing the error code might be useful in some cases.

Change-Id: I52b2c3bc727fa7040f931b1cc1eee3545ef5554e
Reviewed-by: Marco Bubke <marco.bubke@digia.com>
QmlDesigner.PropertyEditor: Do not setup the color in onCompleted

Instead we connect to the selectionChanged signal and do the setup there.

Change-Id: Ia44887fa794c9726b3c4111e1b1f37ba2baaafc5
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>