Improve implicit size of Calendar on high DPI devices.

Task-number: QTBUG-39473
Change-Id: Ibfb1c040efd9744ba6c8bc56affcdf90a807b046
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Do not embed the Desktop style into resources on irrelevant platforms

The Desktop style is not built on these touch/mobile platforms, or when
QtWidgets is not enabled, so it's pointless to embed these QML files.

Change-Id: Iac11473b3a9791745a107e0f7ac1cd34a91a9a5d
Reviewed-by: Liang Qi <liang.qi@digia.com>
Reviewed-by: Andrew Knight <andrew.knight@digia.com>
Reviewed-by: Mitch Curtis <mitch.curtis@digia.com>
Centralize determination of "no desktop" configurations

Change-Id: I030012f48668db4f01737ef92fdb7e6e0426e025
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Liang Qi <liang.qi@digia.com>
Merge remote-tracking branch 'origin/5.3' into dev

Change-Id: Icc15fe685e94dd043979b6b9c6a624f18f2d1e4c