title: Upgrading to Bugzilla 5.0
body: <p>While setting up Bugzilla 5.0, running ./checksetup.pl I ran into this beauty:</p>
  
  <pre><code>Removing existing compiled templates...
  Precompiling templates...done.
  Fixing file permissions...
  Adding foreign key: test_case_components.component_id -&gt;
  components.id...
  DBD::mysql::db do failed: Cannot add foreign key constraint [for Statement "ALTER TABLE test_case_components ADD 
   CONSTRAINT fk_test_case_components_component_id_components_id FOREIGN KEY (component_id)
   REFERENCES components(id)
    ON UPDATE CASCADE ON DELETE CASCADE"] at Bugzilla/DB.pm line 642.
  Bugzilla::DB::bz_add_fks(Bugzilla::DB::Mysql=HASH(0x6c66e10), "test_case_components", HASH(0x61a5f30), HASH(0xa283c48)) called at Bugzilla/DB.pm line 546
  Bugzilla::DB::bz_setup_foreign_keys(Bugzilla::DB::Mysql=HASH(0x6c66e10)) called at Bugzilla/Install/DB.pm line 745
  Bugzilla::Install::DB::update_table_definitions(HASH(0x1522580)) called at ./checksetup.pl line 172
  </code></pre>
  
  <p>Is it due to my database setup? Has anyone else ran into this? If so do you have a patch that worked for you?</p>