fix segfault on UVRASTER layers with mask set (#4779)
avoid segfault on erroneous mask references (#4779)
Fix bug with empty geometrycollections (#4751)
Merge branch 'branch-6-4'
update for rfc104
update submodule
fix segfault on label with failed scale check (#4781)
Fix ISO C90'ism that causes MSVC compilation error
fix rendering of legendicons with 0-length name (#4782)
Merge branch 'b4782-legend-notext'