SplitView: wider splitter on touchscreens

7mm is a typical minimum size for anything meant to be touchable.

Change-Id: Ie29d178495f0b9feae7e76ceaed848301232d2b8
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@digia.com>
Reviewed-by: Jens Bache-Wiig <jens.bache-wiig@digia.com>
QtQuick.Dialogs.Private needs classname in its qmldir

Add classname entry to qmldir, otherwise qmlimportscanner cannot
utilize it when doing static builds (on iOS).  (same as change
6dbb25f944249f7b846be8b4d77165f054c5483f in qtdeclarative)

Task-number: QTBUG-35369
Change-Id: Id4dcd3e2193cd9f76db72f3244b1bde39a0d1a63
Reviewed-by: Liang Qi <liang.qi@digia.com>