Vulkan: Clean up VMA wrapper classes. Make these more consistent with the rest of the wrapper classes. Also handle some VkResult errors that were being ignored. Will pave the way for better handling of buffer allocation error conditions. Bug: chromium:1086532 Change-Id: Idc5b3f0e2945b1f44f152d33e8cc572f83a6b658 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2219136 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Mohan Maiya <m.maiya@samsung.com>