Split "Online" and "Offline" AudioContext processing

Source/modules/webaudio/MediaElementAudioSourceNode.h

Index: Source/modules/webaudio/MediaElementAudioSourceNode.h
diff --git a/Source/modules/webaudio/MediaElementAudioSourceNode.h b/Source/modules/webaudio/MediaElementAudioSourceNode.h
index fc5322306091f1e666564716fc0dd4ab5cb5436f..011d6e5c5e13ab718f14cf5d40f44467a0f320d8 100644
--- a/Source/modules/webaudio/MediaElementAudioSourceNode.h
+++ b/Source/modules/webaudio/MediaElementAudioSourceNode.h
@@ -36,7 +36,7 @@
 
 namespace blink {
 
-class AudioContext;
+class AbstractAudioContext;
 class HTMLMediaElement;
 
 class MediaElementAudioSourceHandler final : public AudioHandler {
@@ -102,7 +102,7 @@ class MediaElementAudioSourceNode final : public AudioSourceNode, public AudioSo
     DEFINE_WRAPPERTYPEINFO();
     USING_GARBAGE_COLLECTED_MIXIN(MediaElementAudioSourceNode);
 public:
-    static MediaElementAudioSourceNode* create(AudioContext&, HTMLMediaElement&);
+    static MediaElementAudioSourceNode* create(AbstractAudioContext&, HTMLMediaElement&);
     DECLARE_VIRTUAL_TRACE();
     MediaElementAudioSourceHandler& mediaElementAudioSourceHandler() const;
 
@@ -115,7 +115,7 @@ public:
     void unlock() override;
 
 private:
-    MediaElementAudioSourceNode(AudioContext&, HTMLMediaElement&);
+    MediaElementAudioSourceNode(AbstractAudioContext&, HTMLMediaElement&);
 };
 
 } // namespace blink