rubocop: disable Rails/ContentTag for migrations

Change-Id: I44d4c789fe539158a74143de6665caa0c6e73977
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/274676
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>
Reviewed-by: Simon Williams <simon@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>

.rubocop.common.yml

@@ -55,6 +55,11 @@ Rails/HasManyOrHasOneDependent:
   Enabled: false # legacy code + most things we soft delete anyway
 Rails/SkipsModelValidations:
   Enabled: false # Canvas skips validations in many places for optimization reasons
+Rails/ContentTag:
+  Severity: error
+  Exclude:
+    - "**/db/migrate/*" # this cop is for views, not migrations, where it gets confused with outrigger
+    - "doc/**/*"
 
 RSpec/DescribedClass:
   Enabled: false # we haven't used it, and it seems antithetical to RSpec/NamedSubject

app/helpers/application_helper.rb

@@ -937,13 +937,13 @@ module ApplicationHelper
 
     output = []
     if @meta_tags.present?
-      output = @meta_tags.map { |meta_attrs| tag("meta", meta_attrs) }
+      output = @meta_tags.map { |meta_attrs| tag.meta(meta_attrs) }
     end
 
     # set this if you want android users of your site to be prompted to install an android app
     # you can see an example of the one that instructure uses in InfoController#web_app_manifest
     manifest_url = Setting.get('web_app_manifest_url', '')
-    output << tag("link", rel: 'manifest', href: manifest_url) if manifest_url.present?
+    output << tag.link(rel: 'manifest', href: manifest_url) if manifest_url.present?
 
     output.join("\n").html_safe.presence
   end

app/helpers/will_paginate_helper.rb

@@ -23,6 +23,7 @@ require 'will_paginate/core_ext'
 require 'will_paginate/view_helpers'
 require 'will_paginate/view_helpers/link_renderer_base'
 
+# rubocop:disable Rails/ContentTag this is not the Rails `tag` method in this file
 module WillPaginateHelper
   class AccessibleLinkRenderer < WillPaginate::ActionView::LinkRenderer
     protected
@@ -54,3 +55,4 @@ module WillPaginateHelper
     end
   end
 end
+# rubocop:enable Rails/ContentTag

lib/canvas/cassandra/migration.rb

@@ -61,7 +61,7 @@ module Canvas
       end
 
       def self.included(migration)
-        migration.tag :cassandra
+        migration.tag :cassandra # rubocop:disable Rails/ContentTag this is Outrigger's tag, not Rails'
         migration.singleton_class.include(ClassMethods)
       end
     end