Session: Minimize direct use of reader when loading sessions

Instead of directly reading things like the project list from the
reader, add a map of "session values" in the session and read these from
the reader once, then use the session to access these values while
loading the details of the session. This is in preparation of separating
the session loading from projectexplorer.

This is similar to Session::(set)Value. We cannot use the same
(set)Value methods directly though, because of differences in the
handling of these values during implict and explicit default session
loading.

Change-Id: I9a4f38a9f958734d20d6e6eb7253f9e44ba1285e
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

0 files changed, 0 insertions, 0 deletions