Update Gaia API documents for #cad1301a64f5d1ecd1a7399d780f7b72a63ad847
    Revert "Merge pull request #14745 from huchengtw-moz/video/Bug_915039_add_cancel_button"

This reverts commit a523c1ee4130a7883981924f8e68fb94be02428a, reversing
changes made to 83688a4f70774f1f96f4621f781024fcc925bce9.