Resolve "Scrolling tabs are broken on profile, activity, and projects"

app/assets/stylesheets/framework/mixins.scss

@@ -186,6 +186,7 @@
   overflow-y: hidden;
   -webkit-overflow-scrolling: touch;
   display: flex;
+  flex-wrap: nowrap;
 
   &::-webkit-scrollbar {
     display: none;

app/assets/stylesheets/framework/secondary_navigation_elements.scss

@@ -230,6 +230,8 @@
 }
 
 .scrolling-tabs-container {
+  position: relative;
+
   .merge-request-tabs-container & {
     overflow: hidden;
   }

app/assets/stylesheets/pages/merge_requests.scss

@@ -678,6 +678,7 @@
 
 .merge-request-tabs {
   display: flex;
+  flex-wrap: nowrap;
   margin-bottom: 0;
   padding: 0;
 }

app/assets/stylesheets/pages/projects.scss

@@ -354,12 +354,6 @@
   min-width: 200px;
 }
 
-.deploy-keys {
-  .scrolling-tabs-container {
-    position: relative;
-  }
-}
-
 .deploy-key {
   // Ensure that the fingerprint does not overflow on small screens
   .fingerprint {

app/views/projects/merge_requests/show.html.haml

@@ -32,8 +32,7 @@
         .scrolling-tabs-container.inner-page-scroll-tabs.is-smaller
           .fade-left= icon('angle-left')
           .fade-right= icon('angle-right')
-          .nav-links.scrolling-tabs.nav.nav-tabs
-            %ul.merge-request-tabs.nav-tabs.nav
+          %ul.merge-request-tabs.nav-tabs.nav.nav-links.scrolling-tabs
             %li.notes-tab
               = tab_link_for @merge_request, :show, force_link: @commit.present? do
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