Rename default_owner to first_owner

We don't want to imply tiers of project/group ownership.
This makes it clear that there may be more than one owner
and this is simply the first one.

app/models/concerns/has_wiki.rb

@@ -17,7 +17,7 @@ module HasWiki
 
   def wiki
     strong_memoize(:wiki) do
-      Wiki.for_container(self, self.default_owner)
+      Wiki.for_container(self, self.first_owner)
     end
   end
 

app/models/group.rb

@@ -726,8 +726,8 @@ class Group < Namespace
     end
   end
 
-  def default_owner
-    owners.first || parent&.default_owner || owner
+  def first_owner
+    owners.first || parent&.first_owner || owner
   end
 
   def default_branch_name

app/models/project.rb

@@ -1513,11 +1513,11 @@ class Project < ApplicationRecord
     group || namespace.try(:owner)
   end
 
-  def default_owner
+  def first_owner
     obj = owner
 
-    if obj.respond_to?(:default_owner)
-      obj.default_owner
+    if obj.respond_to?(:first_owner)
+      obj.first_owner
     else
       obj
     end

app/services/design_management/copy_design_collection/copy_service.rb

@@ -16,7 +16,7 @@ module DesignManagement
         @temporary_branch = "CopyDesignCollectionService_#{SecureRandom.hex}"
         # The user who triggered the copy may not have permissions to push
         # to the design repository.
-        @git_user = @target_project.default_owner
+        @git_user = @target_project.first_owner
 
         @designs = DesignManagement::Design.unscoped.where(issue: issue).order(:id).load
         @versions = DesignManagement::Version.unscoped.where(issue: issue).order(:id).includes(:designs).load

ee/spec/services/ee/git/wiki_push_service_spec.rb

@@ -7,7 +7,7 @@ RSpec.describe Git::WikiPushService do
 
   let_it_be(:key_id) { create(:key, user: current_user).shell_id }
   let_it_be(:wiki) { create(:project_wiki) }
-  let_it_be(:current_user) { wiki.container.default_owner }
+  let_it_be(:current_user) { wiki.container.first_owner }
   let_it_be(:repository) { wiki.repository }
 
   let(:post_received) { ::Gitlab::GitPostReceive.new(wiki.container, key_id, changes, {}) }

spec/factories/wikis.rb

@@ -4,7 +4,7 @@ FactoryBot.define do
   factory :wiki do
     transient do
       container { association(:project) }
-      user { container.default_owner || association(:user) }
+      user { container.first_owner || association(:user) }
     end
 
     initialize_with { Wiki.for_container(container, user) }

spec/models/group_spec.rb

@@ -2539,7 +2539,7 @@ RSpec.describe Group do
     end
   end
 
-  describe '#default_owner' do
+  describe '#first_owner' do
     let(:group) { build(:group) }
 
     context 'the group has owners' do
@@ -2549,7 +2549,7 @@ RSpec.describe Group do
       end
 
       it 'is the first owner' do
-        expect(group.default_owner)
+        expect(group.first_owner)
           .to eq(group.owners.first)
           .and be_a(User)
       end
@@ -2564,8 +2564,8 @@ RSpec.describe Group do
       end
 
       it 'is the first owner of the parent' do
-        expect(group.default_owner)
-          .to eq(parent.default_owner)
+        expect(group.first_owner)
+          .to eq(parent.first_owner)
           .and be_a(User)
       end
     end
@@ -2576,7 +2576,7 @@ RSpec.describe Group do
       end
 
       it 'is the group.owner' do
-        expect(group.default_owner)
+        expect(group.first_owner)
           .to eq(group.owner)
           .and be_a(User)
       end

spec/models/project_spec.rb

@@ -1299,7 +1299,7 @@ RSpec.describe Project, factory_default: :keep do
     end
   end
 
-  describe '#default_owner' do
+  describe '#first_owner' do
     let_it_be(:owner)     { create(:user) }
     let_it_be(:namespace) { create(:namespace, owner: owner) }
 
@@ -1307,7 +1307,7 @@ RSpec.describe Project, factory_default: :keep do
       let(:project) { build(:project, namespace: namespace) }
 
       it 'is the namespace owner' do
-        expect(project.default_owner).to eq(owner)
+        expect(project.first_owner).to eq(owner)
       end
     end
 
@@ -1316,9 +1316,9 @@ RSpec.describe Project, factory_default: :keep do
       let(:project) { build(:project, group: group, namespace: namespace) }
 
       it 'is the group owner' do
-        allow(group).to receive(:default_owner).and_return(Object.new)
+        allow(group).to receive(:first_owner).and_return(Object.new)
 
-        expect(project.default_owner).to eq(group.default_owner)
+        expect(project.first_owner).to eq(group.first_owner)
       end
     end
   end

spec/views/shared/wikis/_sidebar.html.haml_spec.rb

@@ -3,7 +3,7 @@ require 'spec_helper'
 
 RSpec.describe 'shared/wikis/_sidebar.html.haml' do
   let_it_be(:project) { create(:project) }
-  let_it_be(:wiki) { Wiki.for_container(project, project.default_owner) }
+  let_it_be(:wiki) { Wiki.for_container(project, project.first_owner) }
 
   before do
     assign(:wiki, wiki)