Bug 1577821: Add BUG_COMPONENT to launcher process moz.build; r=mhowell

Differential Revision: https://phabricator.services.mozilla.com/D44209

--HG--
extra : moz-landing-system : lando

browser/app/winlauncher/moz.build

@@ -66,3 +66,6 @@ if CONFIG['MOZ_LAUNCHER_PROCESS']:
         DEFINES[var] = '"%s"' % CONFIG[var]
 
 DisableStlWrapping()
+
+with Files('**'):
+    BUG_COMPONENT = ('Firefox', 'Launcher Process')