f0cb31a12 makes SDL_Vulkan_GetDrawableSize not possible to retrieve the correct size after destroying swapchain

[Benau]

The comment there says The drawableSize will be set to a correct size by the next swapchain created on the same surface., but because of getCAMetalLayer().drawableSize = { 1,1 }; , SDL_Vulkan_GetDrawableSize will return 1, 1 which affects application using that function to retrieve the real screen size to fill the swapchain creation parameters when the surface is unchanged (ie window size unchanged),

Example:
https://github.com/supertuxkart/stk-code/blob/ad25726263556b50bf56fcb52884bc700b6259de/lib/graphics_engine/src/ge_vulkan_driver.cpp#L1256

Maybe you can avoid forceUnpresentedImageCompletion after vkDeviceWaitIdle?

[Benau]

Actually the currentExtent in SurfaceCapabilities already does the job (even takes half-to-even rounding into account), you can see if you want to fix the compatibility with SDL or not