qt: Allow deferred start of import job
* lang/qt/src/importjob.h (ImportJob::startLater): New pure virtual method. * lang/qt/src/qgpgmeimportjob.cpp, lang/qt/src/qgpgmeimportjob.h (QGpgMEImportJob::startLater): New method. * lang/qt/tests/t-import.cpp (ImportTest::testDeferredStart): New.
This makes it possible to prepare an import job for a deferred start.
- GnuPG-bug-id: T6323