remove superfluous "collapsed" class and rename header classes for clarity

app/assets/javascripts/sidebar.js.es6

@@ -14,11 +14,9 @@
 
   const pinnedPageClass = 'page-sidebar-pinned';
   const expandedPageClass = 'page-sidebar-expanded';
-  const collapsedPageClass = 'page-sidebar-collapsed';
 
-  const pinnedNavbarClass = 'header-pinned-nav';
-  const expandedNavbarClass = 'header-expanded';
-  const collapsedNavbarClass = 'header-collapsed';
+  const pinnedNavbarClass = 'header-sidebar-pinned';
+  const expandedNavbarClass = 'header-sidebar-expanded';
 
   class Sidebar {
     constructor() {
@@ -75,12 +73,10 @@
     renderState() {
       $(pageSelector)
         .toggleClass(pinnedPageClass, this.isPinned && this.isExpanded)
-        .toggleClass(expandedPageClass, this.isExpanded)
-        .toggleClass(collapsedPageClass, !this.isExpanded);
+        .toggleClass(expandedPageClass, this.isExpanded);
       $(navbarSelector)
         .toggleClass(pinnedNavbarClass, this.isPinned && this.isExpanded)
-        .toggleClass(expandedNavbarClass, this.isExpanded)
-        .toggleClass(collapsedNavbarClass, !this.isExpanded);
+        .toggleClass(expandedNavbarClass, this.isExpanded);
 
       const $pinnedToggle = $(pinnedToggleSelector);
       const tooltipText = this.isPinned ? 'Unpin navigation' : 'Pin navigation';

app/assets/stylesheets/framework/header.scss

@@ -77,10 +77,6 @@ header {
       }
     }
 
-    &.header-collapsed {
-      padding: 0 16px;
-    }
-
     .side-nav-toggle {
       position: absolute;
       left: -10px;

app/assets/stylesheets/framework/sidebar.scss

 .page-with-sidebar {
-  padding-top: $header-height;
-  padding-bottom: 25px;
+  padding: $header-height 0 25px;
   transition: padding $sidebar-transition-duration;
 
   &.page-sidebar-pinned {
@@ -15,6 +14,7 @@
     bottom: 0;
     left: 0;
     height: 100%;
+    width: 0;
     overflow: hidden;
     transition: width $sidebar-transition-duration;
     @include box-shadow(2px 0 16px 0 $black-transparent);
@@ -150,14 +150,6 @@
   }
 }
 
-.page-sidebar-collapsed {
-  padding-left: 0;
-
-  .sidebar-wrapper {
-    width: 0;
-  }
-}
-
 .page-sidebar-expanded {
   .sidebar-wrapper {
     width: $sidebar_width;
@@ -173,7 +165,7 @@
   }
 }
 
-header.header-pinned-nav {
+header.header-sidebar-pinned {
   @media (min-width: $sidebar-breakpoint) {
     padding-left: ($sidebar_width + $gl-padding);
 

app/assets/stylesheets/pages/builds.scss

@@ -48,12 +48,6 @@
       margin-bottom: 10px;
     }
   }
-
-  .page-sidebar-collapsed {
-    .scroll-controls {
-      left: 70px;
-    }
-  }
 }
 
 .build-header {

app/helpers/nav_helper.rb

@@ -14,8 +14,6 @@ module NavHelper
   def page_sidebar_class
     if pinned_nav?
       "page-sidebar-expanded page-sidebar-pinned"
-    else
-      "page-sidebar-collapsed"
     end
   end
 
@@ -43,9 +41,7 @@ module NavHelper
     class_name << " with-horizontal-nav" if defined?(nav) && nav
 
     if pinned_nav?
-      class_name << " header-expanded header-pinned-nav"
-    else
-      class_name << " header-collapsed"
+      class_name << " header-sidebar-expanded header-sidebar-pinned"
     end
 
     class_name