Inject into all descendant processes instead of sub processes to ensure all the descendant processes of Firefox will be hooked with MuterHook on WinXP.
fix bug of win7 crash
remove popmenu from toolbar botton
fix bug of QzoneMusic in Win7

Signed-off-by: JiaoFeng <fjiao@mozilla.com>
Merge branch 'jiaofeng' of github.com:yxl/Firefox-Muter into rebase