[LyX/master] Initialize properly a class member

[Jean-Marc Lasgouttes]

commit ea8f0d2076ad7225d598ba4f171c937624a967c6
Author: Jean-Marc Lasgouttes <lasgout...@lyx.org>
Date:   Wed Mar 1 16:20:52 2017 +0100

    Initialize properly a class member
    
    This was forgotten at 0552563c99, and it only meant to keep coverity happy.
---
 src/Buffer.cpp |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/src/Buffer.cpp b/src/Buffer.cpp
index 892898b..a9b4c05 100644
--- a/src/Buffer.cpp
+++ b/src/Buffer.cpp
@@ -423,7 +423,8 @@ Buffer::Impl::Impl(Buffer * owner, FileName const & file, 
bool readonly_,
          checksum_(0), wa_(0),  gui_(0), undo_(*owner), 
bibinfo_cache_valid_(false),
          bibfile_cache_valid_(false), cite_labels_valid_(false), 
preview_error_(false),
          inset(0), preview_loader_(0), cloned_buffer_(cloned_buffer),
-         clone_list_(0), doing_export(false), parent_buffer(0),
+         clone_list_(0), doing_export(false),
+         tracked_changes_present_(0), parent_buffer(0),
          word_count_(0), char_count_(0), blank_count_(0)
 {
        if (!cloned_buffer_) {