Bug 1518352 remove unnecessary WeakPtr support from PannerNode r=padenot

This is no longer used since https://hg.mozilla.org/mozilla-central/rev/11b4729e92ec#l3.101

Differential Revision: https://phabricator.services.mozilla.com/D15890

--HG--
extra : moz-landing-system : lando

dom/media/webaudio/PannerNode.h

@@ -11,7 +11,6 @@
 #include "AudioParam.h"
 #include "mozilla/dom/PannerNodeBinding.h"
 #include "ThreeDPoint.h"
-#include "mozilla/WeakPtr.h"
 #include <limits>
 #include <set>
 
@@ -22,14 +21,12 @@ class AudioContext;
 class AudioBufferSourceNode;
 struct PannerOptions;
 
-class PannerNode final : public AudioNode, public SupportsWeakPtr<PannerNode> {
+class PannerNode final : public AudioNode {
  public:
   static already_AddRefed<PannerNode> Create(AudioContext& aAudioContext,
                                              const PannerOptions& aOptions,
                                              ErrorResult& aRv);
 
-  MOZ_DECLARE_WEAKREFERENCE_TYPENAME(PannerNode)
-
   static already_AddRefed<PannerNode> Constructor(const GlobalObject& aGlobal,
                                                   AudioContext& aAudioContext,
                                                   const PannerOptions& aOptions,