Blender Git Loki

Cleanup: cross-reference right pointing arrow literal

This value is defined in the UI module, but happens to be used
in string_search.cc too. Note that these references need to be kept in
sync. Use escaped utf-8 sequence since the literal can be avoided.

Also replace BLI_str_utf8_as_unicode calls with constant assignments
as these values are known there is no need to decode a utf-8 sequence.