[fixed]Player damage reduction & planeswalkers

[Nexhro]

Describe the Bug:
Cards that reduce the amount of damage dealt to a player also reduce damage dealt to planeswalkers that player controls. Tested this with Guardian Seraph, Urza's Armor and Battletide Alchemist.

Which card did behave improperly ?
Damage reduction OR Planeswalkers

Which update are you using?(date,name)Which type(Duel,Gauntlet,Sealed Deck)
JOU v1, duel

What exactly should be the correct behavior/interaction ?
Cards that reduce the amount of damage dealt to a player don't reduce damage dealt to planeswalkers that player controls unless it's explicitly stated that damage dealt to planeswalkers/permanents that player controls is prevented.

Are any other cards possibly affected by this bug ?
It's possible that this also occurs in conjunction with prevention spells like for example Solitary Confinement, Personal Sanctuary, Heavy Fog or Riot Control.

[Aswan jaguar]

Fixed Guardian Seraph & Battletide Alchemist mentioned here in commit 0133fa64.
Urza's Armor had already been fixed but it prevented all damage from a source which is also fixed by this commit.
EDIT:
Fixed Riot Control in commit ca5a5cfc. The others are fine.