Resetting all fields for all dims corrupts pivot cache

test case is exporting ooo55266-3 (contains data grouped in numerical
intervals) to xlsx and without closing the document, opening filter on
1st pivot table (kaboom!)

ClearGroupFields corrupts the cache bc it resets Field.mpGroup items
for all dimensions, not just the one present in ScDPDimensionSaveData
(all this happening in ScDPCollection::SheetCaches::getCache).
Consequently, accessing or rebuilding pivot cache may crash bc mpGroup
now points nowhere.

I split and renamed ScDPCache::ClearGroupFields into 2 parts, one of
them clears maGroupFields, the other resets mpGroup ptrs in maFields.
When adding data to cache, the former is used (bc group ptrs get reset
almost immediately afterwards)

Reviewed-on: https://gerrit.libreoffice.org/65329
Tested-by: Jenkins
Reviewed-by: Eike Rathke <erack@redhat.com>
Reviewed-by: Kohei Yoshida <libreoffice@kohei.us>
Reviewed-by: Katarina Behrens <Katarina.Behrens@cib.de>
(cherry picked from commit f70d29fd91d232f0b030f0f76bd23bd2919eb868)

Change-Id: I96e8d234a17da0f3cc65c0625aa47b12284b98b8
Reviewed-on: https://gerrit.libreoffice.org/66622
Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Jenkins

1 files changed, 0 insertions, 0 deletions

diff --git a/sc/qa/unit/data/ods/numgroup_example.ods b/sc/qa/unit/data/ods/numgroup_example.ods
new file mode 100644
index 000000000000..008e1bfd4970
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+++ b/sc/qa/unit/data/ods/numgroup_example.ods