Description: replace the hardcode of "@mozilla.org/embedcomp/window-watcher;1" with NS_WINDOWWATCHER_CONTRACTID
Patch by Henry.Jia@sun.com
r=anto, sr=alecf
Instead of using the static variable in /gfx to maintain the state
of font download (eg. static BOOL gCheckJAFont = PR_FALSE;),
we use a nsFontPackageService::FontPackageHandled() API to allow
resetting of the font download.
/r=ftang; /sr=brendan
