Only save right sidebar position cookie if user did the collapsing.

app/assets/javascripts/application.js.coffee

@@ -225,8 +225,8 @@ $ ->
           $gutterIcon.closest('a').trigger('click')
 
   $(document)
-    .off 'click', '.gutter-toggle'
-    .on 'click', '.gutter-toggle', (e) ->
+    .off 'click', 'aside .gutter-toggle'
+    .on 'click', 'aside .gutter-toggle', (e, manual) ->
       e.preventDefault()
       $this = $(this)
       $thisIcon = $this.find 'i'
@@ -251,6 +251,7 @@ $ ->
         $('.page-with-sidebar')
           .removeClass('right-sidebar-collapsed')
           .addClass('right-sidebar-expanded')
+      if not manual
         $.cookie("collapsed_gutter",
           $('.right-sidebar')
             .hasClass('right-sidebar-collapsed'), { path: '/' })

app/assets/javascripts/merge_request_tabs.js.coffee

@@ -195,6 +195,6 @@ class @MergeRequestTabs
     setTimeout( ->
       # Only when sidebar is collapsed
       if $gutterIcon.is('.fa-angle-double-right')
-        $gutterIcon.closest('a').trigger('click')
+        $gutterIcon.closest('a').trigger('click',[true])
     , 0)