upgrade: move optimization addition to determineactions()

The documentation of `determineactions()` mention that it is given a list
returned from `findoptimizations()` however it was not true before this patch.

The code extending actions with optimizations also mentioned about it that this
should be in determineactions.

So let's do what comments at couple of places say.

Differential Revision: https://phab.mercurial-scm.org/D9615

mercurial/upgrade.py

@@ -85,13 +85,7 b' def upgraderepo('
 
     format_upgrades = upgrade_actions.find_format_upgrades(repo)
     actions = upgrade_actions.determineactions(
-        repo, format_upgrades, repo.requirements, newreqs
-    )
-    actions.extend(
-        o
-        for o in sorted(optimizations)
-        # determineactions could have added optimisation
-        if o not in actions
+        repo, format_upgrades, optimizations, repo.requirements, newreqs
     )
 
     removedreqs = repo.requirements - newreqs

mercurial/upgrade_utils/actions.py

@@ -526,7 +526,9 b' def findoptimizations(repo):'
     return list(ALL_OPTIMISATIONS)
 
 
-def determineactions(repo, format_upgrades, sourcereqs, destreqs):
+def determineactions(
+    repo, format_upgrades, optimizations, sourcereqs, destreqs
+):
     """Determine upgrade actions that will be performed.
 
     Given a list of improvements as returned by ``find_format_upgrades`` and
@@ -551,6 +553,8 b' def determineactions(repo, format_upgrad'
 
         newactions.append(d)
 
+    newactions.extend(o for o in sorted(optimizations) if o not in newactions)
+
     # FUTURE consider adding some optimizations here for certain transitions.
     # e.g. adding generaldelta could schedule parent redeltas.