Add support for "Manage your account" active in the account nav

app/controllers/root_controller.rb

@@ -25,6 +25,7 @@ class RootController < ApplicationController
     campaign
     gem_layout
     gem_layout_account_manager
+    gem_layout_account_manager_manage_your_account_active
     gem_layout_account_manager_no_nav
     gem_layout_explore_header
     gem_layout_full_width

app/views/root/_account.html.erb

@@ -1,10 +1,11 @@
 <%
   omit_account_navigation ||= nil
+  account_nav_location ||= "your-account"
   di_location = "https://signin.account.gov.uk"
 %>
 
 <%= render partial: "gem_base", locals: {
-  account_nav_location: "your-account",
+  account_nav_location: account_nav_location,
   omit_feedback_form: true,
   omit_footer_border: true,
   omit_global_banner: true,

app/views/root/_gem_base.html.erb

@@ -47,6 +47,7 @@
         module: "explicit-cross-domain-links",
         link_for: "accounts-signed-in",
       },
+      active: show_account_layout,
     },
     {
       text: "Sign out",

app/views/root/gem_layout_account_manager_manage_your_account_active.html.erb

@@ -0,0 +1,3 @@
+<%= render partial: "account", locals: {
+  account_nav_location: "manage",
+} %>

docs/slimmer_templates.md

@@ -20,6 +20,9 @@ This layout omits the default feedback component for GOVUK as the account pages
 
 Same as the `gem_layout_account_manager`, but displays without the account nav component.
 
+## `gem_layout_account_manager_manage_your_account_active`
+
+Same as the `gem_layout_account_manager`, but displays "Manage your account" as active in the [account navigation element](https://components.publishing.service.gov.uk/component-guide/layout_for_public/with_current_account_navigation/preview).
 
 ## `core_layout` (default)