don't include account CSS on "Updated Terms" page

fixes CNVS-22527

test-plan:
 - when "Updated Terms of Use" page displays, should not include any
   custom account CSS

Change-Id: I98bcc48e1bf4f281ee34db8ee50ed204defc437d
Reviewed-on: https://gerrit.instructure.com/61659
Reviewed-by: Rob Orton <rob@instructure.com>
Product-Review: Colleen Palmer <colleen@instructure.com>
Reviewed-by: Ryan Shaw <ryan@instructure.com>
Tested-by: Jenkins
QA-Review: August Thornton <august@instructure.com>

app/helpers/application_helper.rb

@@ -705,8 +705,18 @@ module ApplicationHelper
     end
   end
 
+  # allows forcing account CSS off universally for a specific situation,
+  # without requiring the global_includes=0 param
+  def disable_account_css
+    @disable_account_css = true
+  end
+
+  def disable_account_css?
+    @disable_account_css || params[:global_includes] == '0'
+  end
+
   def include_account_css
-    return if params[:global_includes] == '0'
+    return if disable_account_css?
     if use_new_styles? 
       includes = [] 
       includes << brand_config_includes[:css] if  brand_config_includes[:css].present? 

app/views/shared/terms_required.html.erb

@@ -2,6 +2,8 @@
   content_for :page_title, t('updated_terms_of_use', 'Updated Terms of Use')
 
   css_bundle :login
+  disable_account_css
+
   @headers = false
   @body_classes ||= []
   @body_classes << "modal"

spec/views/shared/terms_required.html.erb_spec.rb

@@ -0,0 +1,42 @@
+#
+# Copyright (C) 2015 Instructure, Inc.
+#
+# This file is part of Canvas.
+#
+# Canvas is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Affero General Public License as published by the Free
+# Software Foundation, version 3 of the License.
+#
+# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along
+# with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+
+require File.expand_path(File.dirname(__FILE__) + '/../../spec_helper')
+require File.expand_path(File.dirname(__FILE__) + '/../views_helper')
+
+describe "/shared/terms_required" do
+  context "with custom stylesheet on account" do
+    before do
+      assigns[:domain_root_account] = Account.default
+      expect(Account.default.feature_enabled?(:use_new_styles)).to be_falsey
+      expect(Account.default.feature_enabled?(:k12)).to be_falsey
+      Account.default.settings = {global_includes: true, global_stylesheet: '/custom_stylesheet.css'}
+      Account.default.save!
+    end
+
+    it "should still include application stylesheet" do
+      render template: "shared/terms_required", layout: "layouts/application"
+      expect(response).to match(%r{<link href="[^"]*bundles/login-[^"]*\.css"})
+    end
+
+    it "should not include custom stylesheet" do
+      render template: "shared/terms_required", layout: "layouts/application"
+      expect(response).not_to match(%r{<link href="/custom_stylesheet\.css"})
+    end
+  end
+end