Unify current_fx_name and current_hook_fx_name [2/n]

[carmocca]

What does this PR do?

1/n: #7590
Part of #7183

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[codecov]

Codecov Report

Merging #7594 (f37c1ea) into master (608de6a) will decrease coverage by 0%.
The diff coverage is 94%.

@@          Coverage Diff           @@
##           master   #7594   +/-   ##
======================================
- Coverage      88%     88%   -0%     
======================================
  Files         197     197           
  Lines       12871   12868    -3     
======================================
- Hits        11325   11306   -19     
- Misses       1546    1562   +16     

[tchaton]

LGTM !