[LyX/master] Handle the case where doc_bv is null

[Jean-Marc Lasgouttes]

commit 5a62e37adda7cb1882c048809d39c29bd9f27265
Author: Jean-Marc Lasgouttes <lasgout...@lyx.org>
Date:   Thu Mar 9 14:41:27 2017 +0100

    Handle the case where doc_bv is null
    
    It might only happens in specific cases where no file is open and for
    some reason the new file cannot be opened.
---
 src/frontends/qt4/GuiApplication.cpp |   10 ++++------
 1 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/src/frontends/qt4/GuiApplication.cpp 
b/src/frontends/qt4/GuiApplication.cpp
index 0eb55ba..05b7a25 100644
--- a/src/frontends/qt4/GuiApplication.cpp
+++ b/src/frontends/qt4/GuiApplication.cpp
@@ -1473,9 +1473,7 @@ void GuiApplication::gotoBookmark(unsigned int idx, bool 
openFile,
        // if the current buffer is not that one, switch to it.
        BufferView * doc_bv = current_view_ ?
                current_view_->documentBufferView() : 0;
-       // FIXME It's possible that doc_bv is null!!
-       // See coverity #102061
-       Cursor const old = doc_bv->cursor();
+       Cursor const * old = doc_bv ? &doc_bv->cursor() : 0;
        if (!doc_bv || doc_bv->buffer().fileName() != tmp.filename) {
                if (switchToBuffer) {
                        dispatch(FuncRequest(LFUN_BUFFER_SWITCH, file));
@@ -1487,13 +1485,13 @@ void GuiApplication::gotoBookmark(unsigned int idx, 
bool openFile,
        }
 
        // moveToPosition try paragraph id first and then paragraph (pit, pos).
-       if (!doc_bv->moveToPosition(
+       if (!doc_bv || !doc_bv->moveToPosition(
                        tmp.bottom_pit, tmp.bottom_pos, tmp.top_id, 
tmp.top_pos))
                return;
 
        Cursor & cur = doc_bv->cursor();
-       if (cur != old)
-               notifyCursorLeavesOrEnters(old, cur);
+       if (old && cur != *old)
+               notifyCursorLeavesOrEnters(*old, cur);
 
        // bm changed
        if (idx == 0)