tdf#164493 Update script change algorithm to always make progress HEADmaster

Fixes ofz#385256118 Timeout on ImpEditEngine::InitScriptTypes.

Previously, the script assignment algorithm could backtrack in certain
cases where a script run ends with weak characters that should be
included in the following run. Fuzz testing unearthed a case involving
right-to-left override and a CJK combining mark, which caused the
algorithm to make no progress and hang.

The algorithm now always makes progress on each iteration.

Change-Id: I4da138c51d391c152afcee2428c21dc762a2dafc
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/179888
Tested-by: Jenkins
Reviewed-by: Jonathan Clark <jonathan@libreoffice.org>

0 files changed, 0 insertions, 0 deletions