Implement auto test for (de)serialization of dock widget properties.
Test settings compatibility by importing a hard coded byte array.
Test serialization format and sequence by comparing expected and real
serialization output.
Test dock widget closing behavior (QTBUG-103474) to ensure that
no closing inconsistency is caused by serialization incompatibility.
Extensively document/comment the test to ensure failures can be easily
interpreted in the future.
Task-number: QTBUG-103474
Change-Id: I3c1589c2c291b2ed56334d09b85536d4c7388f92
Pick-to: 6.4 6.3 6.2
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
0c54ac20eb