Fix leaked resources when CSwapChainDx11 is resized Before: https://files.facepunch.com/matt/1b1711b1/Taskmgr_mvUnDuMcc1.png After: https://files.facepunch.com/matt/1b1711b1/Taskmgr_fd19SDW3Xa.png CSwapChainVulkan also flushes scratch rendertargets on resize