Bug 1486565 - Don't initialize cubeb when recording/replaying, r=kinetik.

--HG--
extra : rebase_source : 7b6302026c1f64fa5e92f26bd6162d55888fcfe9

dom/media/CubebUtils.cpp

@@ -421,6 +421,10 @@ cubeb* GetCubebContextUnlocked()
             ("%s: returning null context due to %s!", __func__, PREF_CUBEB_FORCE_NULL_CONTEXT));
     return nullptr;
   }
+  if (recordreplay::IsRecordingOrReplaying()) {
+    // Media is not supported when recording or replaying. See bug 1304146.
+    return nullptr;
+  }
   if (sCubebState != CubebState::Uninitialized) {
     // If we have already passed the initialization point (below), just return
     // the current context, which may be null (e.g., after error or shutdown.)