Bug 345517 - Enable libxul by default (again)... this will probably cause perf problems for the argo-vm builds... that is acceptable, because we're moving to the fx-linux-tbox builds, where libxul is known to improve performance

browser/confvars.sh

@@ -48,3 +48,4 @@ MOZ_APP_VERSION=$FIREFOX_VERSION
 MOZ_NO_XPCOM_OBSOLETE=1
 MOZ_EXTENSIONS_DEFAULT=" xml-rpc inspector gnomevfs reporter"
 # MOZ_APP_DISPLAYNAME will be set by branding/configure.sh
+MOZ_ENABLE_LIBXUL=1