When I first create mozilla/intl/uconv/src/ns{Win,Mac,UNIX}Charset.cpp I create the nsURLProperties as local, use it and cache the result in member data , then release it in the local variable and then delete it because I really need to look at it once. When nhotta add new method to the interface GetDefaultCharsetForLocale, he duplicate to code without making the nsURLProperties as a member data and destroy only in the destructor. This cause performance problem. We create a nsURLProperties once every time we call GetDefaultCharsetForLocale, which is a performace hit. We should move the nsURLProperties as an member data and destory only in the destructor. Fix this and ALL the bugs tracek 30201 can reduce a lot of file reading time.

performance issue, add perf as keyword

> When nhotta add new method to the interface GetDefaultCharsetForLocale, not me, look as cvsblame, http://bonsai.mozilla.org/cvsblame.cgi?file=mozilla/intl/uconv/src/nsWinCharset. cpp

I am sorry that I didn't check cvsblame and just use stupid_ftang_blame to blame nhotta. I take it back. It is tague did that. I will take this back and fix it.

fix and check in for all 3 platforms

Verified.