"flat_key","key","int_value","string_value"
"debug.debug1.key1","debug.debug1.key1",10,"[NULL]"
"debug.debug1.key2","debug.debug1.key2[0]",20,"[NULL]"
"debug.debug1.key2","debug.debug1.key2[1]",21,"[NULL]"
"debug.debug1.key2","debug.debug1.key2[2]",22,"[NULL]"
"debug.debug1.key2","debug.debug1.key2[3]",23,"[NULL]"
"debug.debug1.key3","debug.debug1.key3",30,"[NULL]"
"debug.debug2.key1","debug.debug2.key1",10,"[NULL]"
"debug.debug2.key2","debug.debug2.key2[0]",20,"[NULL]"
"debug.debug2.key2","debug.debug2.key2[1]",21,"[NULL]"
"debug.debug2.key2","debug.debug2.key2[2]",22,"[NULL]"
"debug.debug2.key2","debug.debug2.key2[3]",23,"[NULL]"
"debug.debug2.key3.key31","debug.debug2.key3.key31",31,"[NULL]"
"debug.debug2.key3.key32","debug.debug2.key3.key32",32,"[NULL]"
"debug.debug2.key4","debug.debug2.key4",40,"[NULL]"
"debug.debug3","debug.debug3",32,"[NULL]"
"debug.debug4.key1","debug.debug4.key1",10,"[NULL]"
"debug.debug4.key2","debug.debug4.key2[0]",20,"[NULL]"
"debug.debug4.key2","debug.debug4.key2[1]",21,"[NULL]"
"event.category","event.category","[NULL]","cat"
"event.category","event.category","[NULL]","cat"
"event.name","event.name","[NULL]","[NULL]"
"event.name","event.name","[NULL]","name1"
"is_root_in_scope","is_root_in_scope",1,"[NULL]"
"legacy_event.passthrough_utid","legacy_event.passthrough_utid",1,"[NULL]"
"source","source","[NULL]","chrome"
"source","source","[NULL]","descriptor"
"source_id","source_id",1,"[NULL]"
"source_id","source_id",1234,"[NULL]"
"source_id_is_process_scoped","source_id_is_process_scoped",0,"[NULL]"
"source_scope","source_scope","[NULL]","cat"