Add request HistoryElement for deleted state

This fixes openSUSE#3074

src/api/app/models/bs_request.rb

@@ -538,6 +538,8 @@ def change_state(opts)
         history = HistoryElement::RequestReopened
       when "new" then
         history = HistoryElement::RequestReopened
+      when "deleted" then
+        history = HistoryElement::RequestDeleted
       else
         raise RuntimeError, "Unhandled state #{opts[:newstate]} for history"
       end

src/api/app/models/history_element.rb

@@ -131,6 +131,16 @@ def description
   end
 end
 
+class HistoryElement::RequestDeleted < HistoryElement::Request
+  def color
+    'red'
+  end
+
+  def description
+    'Request got deleted'
+  end
+end
+
 class HistoryElement::Review < ::HistoryElement::Base
   self.description = 'Review was updated'
   self.abstract_class = true

src/api/spec/factories/history_elements.rb

@@ -18,4 +18,8 @@
   factory :history_element_request_revoked, class: 'HistoryElement::RequestRevoked' do
     type { 'HistoryElement::RequestRevoked' }
   end
+
+  factory :history_element_request_deleted, class: 'HistoryElement::RequestDeleted' do
+    type { 'HistoryElement::RequestDeleted' }
+  end
 end