Metal: Reuse UBO conversion buffer only if size matches BufferMtl::getUniformConversionBuffer will recycle an existing buffer if the request has the same buffer index and offset that is a multiple of existing block size. This disregards the GL std size of the request leading to incorrect allocation of blocks in the conversion buffer. The fix is to create a new conversion buffer when stdSize != buffer.uniformBufferBlockSize. Bug: angleproject:8393 Change-Id: Ife87309e66f65baa7f636b734a5586d0ae3b9768 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4995450 Reviewed-by: Yuly Novikov <ynovikov@chromium.org> Commit-Queue: Yuly Novikov <ynovikov@chromium.org> Reviewed-by: Quyen Le <lehoangquyen@chromium.org>