Delete the PreferenceMACs on profile deletion.

components/prefs/pref_service.h

Index: components/prefs/pref_service.h
diff --git a/components/prefs/pref_service.h b/components/prefs/pref_service.h
index a360afa44acccffed83987110e086ae7c2ff70fd..724fc52e101dbe80072233a8e657136da1e80d4c 100644
--- a/components/prefs/pref_service.h
+++ b/components/prefs/pref_service.h
@@ -307,6 +307,10 @@ class COMPONENTS_PREFS_EXPORT PrefService : public base::NonThreadSafe {
   // Clears mutable values.
   void ClearMutableValues();
 
+  // Called during profile deletion to allow for deletion of pref-related data
+  // stored outside of the profile directory.
+  void CleanupForProfileDeletion();

[gab, 2017/06/05 17:28:57]

// Invoked when the store is deleted from disk. Allows this PrefService 
// to tangentially cleanup data it may have saved outside the store.
void OnStoreDeletionFromDisk();

(everywhere)


1) components/prefs isn't aware of "profiles"
2) although we can hint at that in the comment, the method name itself shouldn't
enforce that this signal be used strictly for cleanup

[proberge, 2017/06/05 21:22:11]

Done.

+
  protected:
   // The PrefNotifier handles registering and notifying preference observers.
   // It is created and owned by this PrefService. Subclasses may access it for