Fix file sync error with Hola extension enabled
Fix file sync error with Hola extension enabled

With Hola enabled, uploads were failing with NS_BASE_STREAM CLOSED -- it
seems to do something that causes the stream to be read more than once.
Adding REOPEN_ON_REWIND fixes this.

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