Thanks to Zhangyuan from Alibaba for pointing out this bug.

btr_page_empty(): When a clustered index root page is emptied,
preserve PAGE_ROOT_AUTO_INC. This would occur during a page split.

page_create_empty(): Preserve PAGE_ROOT_AUTO_INC when a clustered
index root page becomes empty. Use a faster method for writing
the field.

page_zip_copy_recs(): Reset PAGE_MAX_TRX_ID when copying
clustered index pages. We must clear the field when the root page
was a leaf page and it is being split, so that PAGE_MAX_TRX_ID
will continue to be 0 in clustered index non-root pages.

page_create_zip(): Add debug assertions for validating
PAGE_MAX_TRX_ID and PAGE_ROOT_AUTO_INC.