Extract EE specific files/lines for lib/gitlab (harder but less)

We have the following files containing EE specific code. We should move them to ee/

lib/gitlab/git_access.rb

diff --git a/lib/gitlab/git_access.rb b/home/yorickpeterse/Projects/gitlab/gdk-ee/gitlab/lib/gitlab/git_access.rb
index 010bd0e520c..dc3ca042781 100644
--- a/lib/gitlab/git_access.rb
+++ b/home/yorickpeterse/Projects/gitlab/gdk-ee/gitlab/lib/gitlab/git_access.rb
@@ -4,6 +4,9 @@
 # class return an instance of `GitlabAccessStatus`
 module Gitlab
   class GitAccess
+    prepend ::EE::Gitlab::GitAccess # rubocop: disable Cop/InjectEnterpriseEditionModule
+    include ActionView::Helpers::SanitizeHelper
+    include PathLocksHelper
     include Gitlab::Utils::StrongMemoize
 
     UnauthorizedError = Class.new(StandardError)
@@ -246,18 +249,22 @@ module Gitlab
       end
     end
 
+    # TODO: please clean this up
     def check_push_access!
       if project.repository_read_only?
+        # The repository is temporarily read-only. Please try again later.
         raise UnauthorizedError, ERROR_MESSAGES[:read_only]
       end
 
       if deploy_key?
         unless deploy_key.can_push_to?(project)
+          # This deploy key does not have write access to this project.
           raise UnauthorizedError, ERROR_MESSAGES[:deploy_key_upload]
         end
       elsif user
         # User access is verified in check_change_access!
       else
+        # You are not allowed to upload code for this project.
         raise UnauthorizedError, ERROR_MESSAGES[:upload]
       end

lib/gitlab/usage_data.rb

diff --git a/lib/gitlab/usage_data.rb b/home/yorickpeterse/Projects/gitlab/gdk-ee/gitlab/lib/gitlab/usage_data.rb
index 0101ccc046a..a671d42104d 100644
--- a/lib/gitlab/usage_data.rb
+++ b/home/yorickpeterse/Projects/gitlab/gdk-ee/gitlab/lib/gitlab/usage_data.rb
@@ -5,6 +5,8 @@ module Gitlab
     APPROXIMATE_COUNT_MODELS = [Label, MergeRequest, Note, Todo].freeze
 
     class << self
+      prepend EE::Gitlab::UsageData # rubocop: disable Cop/InjectEnterpriseEditionModule
+
       def data(force_refresh: false)
         Rails.cache.fetch('usage_data', force: force_refresh, expires_in: 2.weeks) { uncached_data }
       end
@@ -29,7 +31,7 @@ module Gitlab
           installation_type: Gitlab::INSTALLATION_TYPE,
           active_user_count: count(User.active),
           recorded_at: Time.now,
-          edition: 'CE'
+          edition: 'EE'
         }
 
         usage_data