[pan2] Fix error found by valgrind: Conditional jump or move depends on uninitialised value(s)

[Petr Kovář <pmkovar src gnome org>]

commit cb9c937b3ff45546dd66a01b71943d69f5027897
Author: Olaf Seibert <rhialto falu nl>
Date:   Sun Mar 13 21:53:48 2016 +0100

    Fix error found by valgrind: Conditional jump or move depends on uninitialised value(s)
    
    Conditional jump or move depends on uninitialised value(s)
       at 0x4E4C64: pan::DataImpl::save_newsrc_files(pan::DataIO&) const (groups.cc:197)
       by 0x4E1EB6: pan::DataImpl::save_state() (data-impl.cc:129)
       by 0x4E16AB: pan::DataImpl::~DataImpl() (data-impl.cc:119)
       by 0x4E1C2A: pan::DataImpl::~DataImpl() (data-impl.cc:118)
       by 0x476D25: main (pan.cc:1142)

 pan/data-impl/data-impl.cc |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/pan/data-impl/data-impl.cc b/pan/data-impl/data-impl.cc
index ee940a3..fc2dbf3 100644
--- a/pan/data-impl/data-impl.cc
+++ b/pan/data-impl/data-impl.cc
@@ -78,6 +78,7 @@ DataImpl :: DataImpl (const StringView& cache_ext, Prefs& prefs, bool unit_test,
   _descriptions_loaded (false),
   newsrc_autosave_id (0),
   newsrc_autosave_timeout (0),
+  in_newsrc_cb (false),
   _rules_filter (prefs.get_flag("rules-autocache-mark-read", false),
                  prefs.get_flag("rules-auto-dl-mark-read", false),
                  prefs.get_flag("rules-autocache-mark-read", false))