tests/org.eclipse.core.tests.runtime/Plugin_Testing/orphan.1/testa/plugin.xml

<?xml version="1.0" encoding="UTF-8"?>
<plugin
  name="Core Runtime Orphan Test 1 A"
  id="testa"
  version="1.0.0"
  vendor-name="OTI">

  <requires>
     <import plugin="testb"/>
     <import plugin="testc"/>
  </requires>

</plugin>