Not counting the decade’s largest acquisition deal, the $57-billion Occidental takeover of Anadarko, 2019 saw only $39 billion in oil and gas deals. But if the $11 billion deals in December alone are anything to go by, 2020 is on track to be another major year for M&A in the industry. And it’s all about the Permian basin--still. That’s because the bigger players in the American shale patch are still hunting for cheap assets from their fellow operators who can’t stand the heat of shareholder pressure to deliver…