message: Fix calculation of scalar struct size (it's not aligned up to alignment)
diff: @@ -397,7 +397,11 @@ StructSizes CalculateStructProps(uint32_t emptyStructSize, const ShaderConstant
  if(i + 1 == c.type.members.size())
  {
  - ret.scalarSize = AlignUp(m.byteOffset + member.scalarSize, ret.scalarAlign);
  + // scalar struct sizes are NOT padded up to the multiple of their alignment. It is allowed
  + // in scalar packing for an outside variable to 'sit in' the padding at the end of a struct
  + // due to alignment. This rule is more tight than even C packing, which normally has
  + // sizeof(struct) be a multiple of its alignment
  + ret.scalarSize = m.byteOffset + member.scalarSize;
  ret.baseSize = AlignUp(m.byteOffset + member.baseSize, ret.baseAlign);
  ret.extendedSize = AlignUp16(m.byteOffset + member.extendedSize);
  }
  