Bug 1356334: Follow-up: Fix debug build bustage.

MozReview-Commit-ID: FxSARetQBCb

--HG--
extra : rebase_source : 4b05968dec5e0f9b95d80d5c2a456368b68c3336

dom/ipc/ContentPrefs.cpp

@@ -54,6 +54,7 @@ const char* mozilla::dom::ContentPrefs::gInitPrefs[] = {
   "dom.ipc.processPriorityManager.backgroundPerceivableGracePeriodMS",
   "dom.ipc.useNativeEventProcessing.content",
   "dom.max_chrome_script_run_time",
+  "dom.max_ext_content_script_run_time",
   "dom.max_script_run_time",
   "dom.mozBrowserFramesEnabled",
   "dom.performance.enable_notify_performance_timing",