HTML 5本地存储子域的大小限制

User agents should guard against sites storing data under their origin's otheraffiliated sites, e.g. storing up to the limit in a1.example.com,a2.example.com,a3.example.com, etc, circumventing the mainexample.com storage limit.

A mostly arbitrary limit of five megabytes per origin is suggested.Implementation feedback is welcome and will be used to update this suggestionin the future.