Merge branch 'frozen-string-enable-app-models' into 'master'

Enable frozen string in app/models/*.rb

See merge request gitlab-org/gitlab-ce!20851

app/models/global_label.rb

+# frozen_string_literal: true
+
 class GlobalLabel
   attr_accessor :title, :labels
   alias_attribute :name, :title

app/models/global_milestone.rb

+# frozen_string_literal: true
+
 class GlobalMilestone
   include Milestoneish

app/models/gpg_key.rb

+# frozen_string_literal: true
+
 class GpgKey < ActiveRecord::Base
   KEY_PREFIX = '-----BEGIN PGP PUBLIC KEY BLOCK-----'.freeze
   KEY_SUFFIX = '-----END PGP PUBLIC KEY BLOCK-----'.freeze

app/models/gpg_key_subkey.rb

+# frozen_string_literal: true
+
 class GpgKeySubkey < ActiveRecord::Base
   include ShaAttribute

app/models/gpg_signature.rb

+# frozen_string_literal: true
+
 class GpgSignature < ActiveRecord::Base
   include ShaAttribute

app/models/group.rb

+# frozen_string_literal: true
+
 require 'carrierwave/orm/activerecord'
 class Group < Namespace

app/models/group_custom_attribute.rb

+# frozen_string_literal: true
+
 class GroupCustomAttribute < ActiveRecord::Base
   belongs_to :group

app/models/group_label.rb

+# frozen_string_literal: true
+
 class GroupLabel < Label
   belongs_to :group

app/models/group_milestone.rb

+# frozen_string_literal: true
+
 class GroupMilestone < GlobalMilestone
   attr_accessor :group

app/models/guest.rb

+# frozen_string_literal: true
+
 class Guest
   class << self
     def can?(action, subject = :global)

app/models/identity.rb

+# frozen_string_literal: true
+
 class Identity < ActiveRecord::Base
   def self.uniqueness_scope
     :provider

app/models/import_export_upload.rb

+# frozen_string_literal: true
+
 class ImportExportUpload < ActiveRecord::Base
   include WithUploads
   include ObjectStorage::BackgroundMove

app/models/individual_note_discussion.rb

+# frozen_string_literal: true
+
 # A discussion to wrap a single `Note` note on the root of an issue, merge request,
 # commit, or snippet, that is not displayed as a discussion.
 #

app/models/instance_configuration.rb

+# frozen_string_literal: true
+
 require 'resolv'
 class InstanceConfiguration

app/models/internal_id.rb

+# frozen_string_literal: true
+
 # An InternalId is a strictly monotone sequence of integers
 # generated for a given scope and usage.
 #

app/models/issue.rb

+# frozen_string_literal: true
+
 require 'carrierwave/orm/activerecord'
 class Issue < ActiveRecord::Base

app/models/issue_assignee.rb

+# frozen_string_literal: true
+
 class IssueAssignee < ActiveRecord::Base
   belongs_to :issue
   belongs_to :assignee, class_name: "User", foreign_key: :user_id

app/models/issue_collection.rb

+# frozen_string_literal: true
+
 # IssueCollection can be used to reduce a list of issues down to a subset.
 #
 # IssueCollection is not meant to be some sort of Enumerable, instead it's meant

app/models/key.rb

+# frozen_string_literal: true
+
 require 'digest/md5'
 class Key < ActiveRecord::Base

app/models/label.rb

+# frozen_string_literal: true
+
 class Label < ActiveRecord::Base
   include CacheMarkdownField
   include Referable