By Foo Yun Chee BRUSSELS (Reuters) -EU countries and EU lawmakers are set to agree on a common charging port for mobile phones, tablets and headphones on June 7 when they meet to discuss a proposal that has been fiercely criticised by Apple, people familiar with the matter said. The proposal for a single mobile charging port was first broached by the European Commission more than a decade ago after iPhone and Android users complained about having to use different chargers for their phones. The former is charged from a Lightning cable while Android-based devices are powered using USB-C connecto…