Copied from: https://hg.mozilla.org/releases/mozilla-esr38/rev/6d43ff33bd55
Security advisory: https://www.mozilla.org/en-US/security/advisories/mfsa2016-01/
Mozilla Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1223670

# HG changeset patch
# User Karl Tomlinson <karlt+@karlt.net>
# Date 1451362442 -46800
# Node ID 6d43ff33bd552b8f7a34e4105cf5bcc0a8c8ea8c
# Parent  f746c38d160ea29088c15cacae44f3662befaec5
bug 1223670 throw not supported when creating a node from a stream with different channel r=baku a=abillings

diff --git a/dom/media/webaudio/MediaStreamAudioSourceNode.cpp b/dom/media/webaudio/MediaStreamAudioSourceNode.cpp
--- a/dom/media/webaudio/MediaStreamAudioSourceNode.cpp
+++ b/dom/media/webaudio/MediaStreamAudioSourceNode.cpp
@@ -51,21 +51,29 @@ MediaStreamAudioSourceNode::Create(Audio
   }
 
   return node.forget();
 }
 
 void
 MediaStreamAudioSourceNode::Init(DOMMediaStream* aMediaStream, ErrorResult& aRv)
 {
+  MOZ_ASSERT(aMediaStream);
+  MediaStream* inputStream = aMediaStream->GetStream();
+  MediaStreamGraph* graph = Context()->Graph();
+  if (NS_WARN_IF(graph != inputStream->Graph())) {
+    aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
+    return;
+  }
+
   mInputStream = aMediaStream;
   AudioNodeEngine* engine = new MediaStreamAudioSourceNodeEngine(this);
-  mStream = Context()->Graph()->CreateAudioNodeExternalInputStream(engine);
+  mStream = graph->CreateAudioNodeExternalInputStream(engine);
   ProcessedMediaStream* outputStream = static_cast<ProcessedMediaStream*>(mStream.get());
-  mInputPort = outputStream->AllocateInputPort(aMediaStream->GetStream(),
+  mInputPort = outputStream->AllocateInputPort(inputStream,
                                                MediaInputPort::FLAG_BLOCK_INPUT);
   mInputStream->AddConsumerToKeepAlive(static_cast<nsIDOMEventTarget*>(this));
 
   PrincipalChanged(mInputStream); // trigger enabling/disabling of the connector
   mInputStream->AddPrincipalChangeObserver(this);
 }
 
 MediaStreamAudioSourceNode::~MediaStreamAudioSourceNode()