Bug 1345906 - Add ReloadPrefsCallback for fuzzing.enabled pref. r=jandem

MozReview-Commit-ID: 5lNyaebmt1h

--HG--
extra : rebase_source : 331dcf55caaa662203a501e5d0fa16f692b61793

js/xpconnect/src/XPCJSContext.cpp

@@ -3541,6 +3541,10 @@ XPCJSContext::Initialize()
     ReloadPrefsCallback(nullptr, this);
     Preferences::RegisterCallback(ReloadPrefsCallback, JS_OPTIONS_DOT_STR, this);
 
+#ifdef FUZZING
+    Preferences::RegisterCallback(ReloadPrefsCallback, "fuzzing.enabled", this);
+#endif
+
     return NS_OK;
 }