Fix missing tabs in touch example
Fix missing tabs in touch example

The only reason that the we calculated the tab count
explicitly before was that we were using an array.
Now that we are using a model there is no longer any
need to keep track of the count independently of the model.

This fix prevents the count from originally showing as 0 and
prevents an extra value change. In addition the count
is now correctly marked as readonly.

Task-number: QTBUG-38421
Change-Id: I53a5d0df3367c850a7c6846729660dd0f63238d5
Reviewed-by: J-P Nurmi <b84a892f57a298bb5dae653b4e188948a84d5549@digia.com>
Reviewed-by: Jonathan Liu <44960b6aa03eb2fb89c62409a43f0b56d13ff84f@gmail.com>

mizukusak/qtquickcontrols,mizukusak/qtquickcontrols,mizukusak/qtquickcontrols