Change isSameNode() to === for Fx10 compatibility
Change isSameNode() to === for Fx10 compatibility

I didn't test this (since it's in annotation code), but according to
https://bugzilla.mozilla.org/show_bug.cgi?id=687400 they're equivalent.

gracile-fr/zotero,gracile-fr/zotero,LinuxMercedes/zotero,rmzelle/zotero,sendecomp/zotero,robamler/zotero,hoehnp/zotero,hoehnp/zotero,adunning/zotero,adunning/zotero,gracile-fr/zotero,egh/zotero,sendecomp/zotero,LinuxMercedes/zotero,aurimasv/zotero,hoehnp/zotero,sendecomp/zotero,rmzelle/zotero,egh/zotero,rmzelle/zotero,retorquere/zotero,egh/zotero,retorquere/zotero,fbennett/zotero,adunning/zotero,retorquere/zotero,robamler/zotero,LinuxMercedes/zotero,robamler/zotero