[LyX/2.1.x] Do not crash when entering math in ct mode with merge dialog open.

[Richard Heck]

commit 90ce24a38d27f48b4f9c9bfc50e06407c4f2f748
Author: Juergen Spitzmueller <sp...@lyx.org>
Date:   Sun Mar 23 09:52:32 2014 +0100

    Do not crash when entering math in ct mode with merge dialog open.
    
    Fixes: #7685.

diff --git a/src/BufferView.cpp b/src/BufferView.cpp
index 7555f78..1398a11 100644
--- a/src/BufferView.cpp
+++ b/src/BufferView.cpp
@@ -684,6 +684,10 @@ Change const BufferView::getCurrentChange() const
                return Change(Change::UNCHANGED);
 
        DocIterator dit = d->cursor_.selectionBegin();
+       // The selected content might have been changed (see #7685)
+       while (dit.inMathed())
+               // Find enclosing text cursor
+               dit.pop_back();
        return dit.paragraph().lookupChange(dit.pos());
 }
 
diff --git a/status.21x b/status.21x
index 18744c4..313985f 100644
--- a/status.21x
+++ b/status.21x
@@ -60,6 +60,9 @@ What's new
 
 * USER INTERFACE
 
+- Fix crash when entering math in change-tracking mode while merge changes
+  dialog is open (bug 7685).
+
 - Failed instant preview compilation now returns an error. And a red box is 
   drawn around very small preview imagines, so they can be seen (bug 7522).