Make default sorting preference work for Issues and MRs.

app/controllers/application_controller.rb

@@ -410,10 +410,8 @@ class ApplicationController < ActionController::Base
   private
 
   def set_default_sort
-    key = if is_a_listing_page_for?('issues')
-            'issues_sort'
-          elsif is_a_listing_page_for?('merge_requests')
-            'merge_requests_sort'
+    key = if is_a_listing_page_for?('issues') || is_a_listing_page_for?('merge_requests')
+            'issuable_sort'
           end
 
     cookies[key]  = params[:sort] if key && params[:sort].present?

features/project/issues/issues.feature

@@ -68,6 +68,13 @@ Feature: Project Issues
     Then The list should be sorted by "Oldest updated"
 
   @javascript
+  Scenario: Visiting Merge Requests after being sorted the list
+    Given I visit project "Shop" issues page
+    And I sort the list by "Oldest updated"
+    And I visit project "Shop" merge requests page
+    Then The list should be sorted by "Oldest updated"
+
+  @javascript
   Scenario: Visiting Merge Requests from a differente Project after sorting
     Given I visit project "Shop" merge requests page
     And I sort the list by "Oldest updated"

features/project/merge_requests.feature

@@ -93,6 +93,13 @@ Feature: Project Merge Requests
     Then The list should be sorted by "Oldest updated"
 
   @javascript
+  Scenario: Visiting Issues after being sorted the list
+    Given I visit project "Shop" merge requests page
+    And I sort the list by "Oldest updated"
+    And I visit project "Shop" issues page
+    Then The list should be sorted by "Oldest updated"
+
+  @javascript
   Scenario: Visiting Merge Requests from a differente Project after sorting
     Given I visit project "Shop" merge requests page
     And I sort the list by "Oldest updated"