Add missing struct definition.
Add missing struct definition.

sunminghong/ffjson,trigrass2/ffjson,xiuzhifu/ffjson,pquerna/ffjson,cw2018/ffjson,cmeon/ffjson,xyliuke/ffjson,xladykiller/ffjson,jamesliu96/ffjson,xiuzhifu/ffjson,cmeon/ffjson,jamesliu96/ffjson,trigrass2/ffjson,pquerna/ffjson,xladykiller/ffjson,cw2018/ffjson,xyliuke/ffjson,sunminghong/ffjson