Reset columns_selector before caching the page

This will allow to initialize this module again without duplicating
columns checkboxes and without breaking the page.

app/assets/javascripts/application.js

@@ -170,6 +170,7 @@ var initialize_modules = function() {
 var destroy_non_idempotent_modules = function() {
   "use strict";
 
+  App.ColumnsSelector.destroy();
   App.Datepicker.destroy();
   App.HTMLEditor.destroy();
   App.LegislationAnnotatable.destroy();

app/assets/javascripts/columns_selector.js

@@ -85,6 +85,9 @@
       $(".column-selectable").on("inserted", function() {
         App.ColumnsSelector.initColumns();
       });
+    },
+    destroy: function() {
+      $("#js-columns-selector-wrapper").children(":not(#column_selector_item_template)").remove();
     }
   };
 }).call(this);

spec/system/admin/budget_investments_spec.rb

@@ -1877,5 +1877,27 @@ describe "Admin budget investments" do
         expect(page).not_to have_content "Don't display me, please!"
       end
     end
+
+    scenario "When restoring the page from browser history renders columns selectors only once", :js do
+      visit admin_budget_budget_investments_path(budget)
+
+      click_link "Proposals"
+
+      expect(page).to have_content("There are no proposals.")
+
+      go_back
+
+      within("#js-columns-selector") do
+        find("strong", text: "Columns").click
+      end
+
+      within("#js-columns-selector-wrapper") do
+        selectable_columns.each do |column|
+          check_text = I18n.t("admin.budget_investments.index.list.#{column}")
+
+          expect(page).to have_content(check_text, count: 1)
+        end
+      end
+    end
   end
 end