Bug 1158887 - Skip test_async_transactions.js on Windows XP for frequent failures. r=mak

toolkit/components/places/tests/unit/xpcshell.ini

@@ -67,6 +67,7 @@ skip-if = os == "android"
 skip-if = os == "android"
 [test_async_history_api.js]
 [test_async_transactions.js]
+skip-if = (os == "win" && os_version == "5.1") # Bug 1158887
 [test_autocomplete_stopSearch_no_throw.js]
 [test_bookmark_catobs.js]
 [test_bookmarks_json.js]