FIX: don't trigger 'flag_reviewed' when no flags were reviewed

spec/integration/flags_spec.rb

@@ -0,0 +1,18 @@
+require "rails_helper"
+
+describe PostAction do
+
+  it "triggers the 'flag_reviewed' event when there was at least one flag" do
+    admin = Fabricate(:admin)
+
+    post = Fabricate(:post)
+    events = DiscourseEvent.track_events { PostDestroyer.new(admin, post).destroy }
+    expect(events.map { |e| e[:event_name] }).to_not include(:flag_reviewed)
+
+    flagged_post = Fabricate(:post)
+    PostAction.act(admin, flagged_post, PostActionType.types[:spam])
+    events = DiscourseEvent.track_events { PostDestroyer.new(admin, flagged_post).destroy }
+    expect(events.map { |e| e[:event_name] }).to include(:flag_reviewed)
+  end
+
+end