changes some code in nsLivemarkService::Init to use it, which gets rid of a handful of nsSimpleURI reference leaks when using the LivemarkService. bug=333784 r=brettw@google.com sr=bryner@brianryner.com git-svn-id: svn://10.0.0.236/branches/MOZILLA_1_8_BRANCH@194291 18797224-902f-48f8-a5cc-f745e15eee43