FEATURE: Show votes in an "on voted" poll to the creator

This required properly plumbing the guardian into the serializer.

Notably, the default state in the client was not changed - if you haven't voted in
the poll, you need to click the button to view the results instead of the results
being immediately visible on page load.

Implements https://meta.discourse.org/t/-/138108

plugins/poll/app/models/poll.rb

@@ -47,7 +47,11 @@ class Poll < ActiveRecord::Base
 
   def can_see_results?(user)
     return !!user&.staff? if staff_only?
-    !!(always? || (on_vote? && has_voted?(user)) || is_closed?)
+    !!(always? || (on_vote? && (is_me?(user) || has_voted?(user))) || is_closed?)
+  end
+
+  def is_me?(user)
+    user && post.user&.id == user&.id
   end
 
   def has_voted?(user)

plugins/poll/app/serializers/poll_serializer.rb

@@ -61,7 +61,7 @@ class PollSerializer < ApplicationSerializer
   end
 
   def include_preloaded_voters?
-    object.can_see_voters?(scope)
+    object.can_see_voters?(scope.user)
   end
 
 end