cleanup some minor compiler warnings
Add missing ChannelizedDropArea.qml to CMake QML_FILES

Change-Id: Ibe0d01cce17ef3e4be3c8120a635c4d9bb5e2598
Reviewed-on: https://codereview.kdab.com/11283
Reviewed-by: Continuous Integration <build@kdab.com>
Reviewed-by: Volker Krause <volker@kdab.com>
Print error-details on setSource errors

Helps to know what exactly went wrong while
hacking on the QML.

Change-Id: Ie2be9603dbd03faac6abe87a6268bacdf2b31597
Reviewed-on: https://codereview.kdab.com/11273
Reviewed-by: Volker Krause <volker@kdab.com>
Implement correct positioning on drag and drop

Change-Id: I7086a7f38915f5e38ccbb7e64e977bdb02de3eed
Reviewed-on: https://codereview.kdab.com/10971
Reviewed-by: Continuous Integration <build@kdab.com>
Reviewed-by: Volker Krause <volker@kdab.com>
Enable drag/drop accepted and fix sender

1. Bug https://bugreports.qt-project.org/browse/QTBUG-39453
is fixed with https://codereview.qt-project.org/#/c/88612/
So, enable the accepted=false case to make rejecting
work.

2. Also add the same for dropping.

3. In ChannelizedDropArea root.item is always undefined.
Use drag/drop.source.dragData.item which contains the
proper sender item. Note that dragData is undefined if
drag and drop happens from the PaletteWidget.

Change-Id: I7fefa2df94761268048f7c9af6b822c6bc5d4cf5
Reviewed-on: https://codereview.kdab.com/11285
Reviewed-by: Continuous Integration <build@kdab.com>
Reviewed-by: Volker Krause <volker@kdab.com>