Prevent unnecessary key transformations, resolves #2704

The database master key settings widget does not actually
need to (re-)transform the master key, it only needs to update
the Key object on the database. Transformation can be deferred
until the Database is persisted to disk. This avoids delays
and unnecessary user interaction with challenge-response
dongles by eliminating redundant key transformations.

src/gui/dbsettings/DatabaseSettingsWidgetEncryption.cpp

@@ -81,7 +81,7 @@ void DatabaseSettingsWidgetEncryption::initialize()
         isDirty = true;
     }
     if (!m_db->key()) {
-        m_db->setKey(QSharedPointer<CompositeKey>::create());
+        m_db->setKey(QSharedPointer<CompositeKey>::create(), true, false, false);
         m_db->setCipher(KeePass2::CIPHER_AES256);
         isDirty = true;
     }