Fixing two migrations that could not be rolled back

when rolling back from 9-0-stable to 8.17.3

db/migrate/20170216141440_drop_index_for_builds_project_status.rb

@@ -3,6 +3,6 @@ class DropIndexForBuildsProjectStatus < ActiveRecord::Migration
   DOWNTIME = false
 
   def change
-    remove_index(:ci_commits, [:gl_project_id, :status])
+    remove_index(:ci_commits, column: [:gl_project_id, :status])
   end
 end

db/migrate/20170305203726_add_owner_id_foreign_key.rb

@@ -5,7 +5,11 @@ class AddOwnerIdForeignKey < ActiveRecord::Migration
 
   disable_ddl_transaction!
 
-  def change
+  def up
     add_concurrent_foreign_key :ci_triggers, :users, column: :owner_id, on_delete: :cascade
   end
+
+  def down
+    remove_foreign_key :ci_triggers, column: :owner_id
+  end
 end