Fix crash when deleting inset with backspace

See description here:
https://marc.info/?l=lyx-devel&m=171243435229412&w=2

cutSelectionHelper did not request a metrics update when the selection
was inner to a paragraph. The new code is better, but it was not
necessary before the biginset branch because of a full metrics
computation that hid this missing case.

(cherry picked from commit 89901123c579c6c7dbd1aecd092d62c3a0a3db24)

diff --git a/src/CutAndPaste.cpp b/src/CutAndPaste.cpp
index 7fd76f98bcbabe0dc622ba95470f47feb7735875..09978d7c506b9d82f41cf03759cfdd787726937c 100644 (file)
--- a/src/CutAndPaste.cpp
+++ b/src/CutAndPaste.cpp
@@ -984,6 +984,8 @@ void cutSelectionHelper(Cursor & cur, CutStack & cuts, bool realcut, bool putcli
 
                if (begpit != endpit)
                        cur.screenUpdateFlags(Update::Force | Update::FitCursor);
+               else
+                       cur.screenUpdateFlags(Update::SinglePar | Update::FitCursor);
 
                tie(endpit, endpos) =
                        eraseSelectionHelper(bp, text->paragraphs(), begpit, endpit,