Vulkan: convert/align vertex data from buffers When we get a buffer with vertex data in an unsupported format or alignment, correct that as we copy it to a DynamicBuffer, then use the copy. Enable tests. BUG=angleproject:2405 Change-Id: I2132abea4d936f6b53d9209be7f99a0e2d8de219 Reviewed-on: https://chromium-review.googlesource.com/1141277 Commit-Queue: Frank Henigman <fjhenigman@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org>