Add OfflineAudioDestinationNode

third_party/WebKit/Source/modules/webaudio/OfflineAudioDestinationNode.cpp

Index: third_party/WebKit/Source/modules/webaudio/OfflineAudioDestinationNode.cpp
diff --git a/third_party/WebKit/Source/modules/webaudio/OfflineAudioDestinationNode.cpp b/third_party/WebKit/Source/modules/webaudio/OfflineAudioDestinationNode.cpp
index e5042117c0f7b54b8b426113049dcd9a7cc06840..e0501cd6820662207732e3e95546c768f5a9b7fc 100644
--- a/third_party/WebKit/Source/modules/webaudio/OfflineAudioDestinationNode.cpp
+++ b/third_party/WebKit/Source/modules/webaudio/OfflineAudioDestinationNode.cpp
@@ -24,6 +24,8 @@
 
 #include "modules/webaudio/OfflineAudioDestinationNode.h"
 
+#include "core/dom/ExceptionCode.h"
+#include "core/dom/ExecutionContext.h"
 #include "core/dom/ExecutionContextTask.h"
 #include "modules/webaudio/AudioNodeInput.h"
 #include "modules/webaudio/AudioNodeOutput.h"
@@ -313,6 +315,40 @@ bool OfflineAudioDestinationHandler::renderIfNotSuspended(AudioBus* sourceBus, A
     return false;
 }
 
+void OfflineAudioDestinationHandler::setChannelCount(unsigned long newChannelCount, ExceptionState& exceptionState)
+{
+    DCHECK(isMainThread());
+    BaseAudioContext::AutoLocker locker(context());
+
+    // Cannot change the channelCount to a different value.
+    if (newChannelCount != channelCount()) {
+        exceptionState.throwDOMException(
+            NotSupportedError,
+            ExceptionMessages::indexOutsideRange<unsigned long>(
+                "channelCount",
+                newChannelCount,
+                channelCount(),
+                ExceptionMessages::InclusiveBound,
+                channelCount(),
+                ExceptionMessages::InclusiveBound));
+    }
+}
+
+void OfflineAudioDestinationHandler::setChannelCountMode(const String& mode, ExceptionState& exceptionState)
+{
+    DCHECK(isMainThread());
+    BaseAudioContext::AutoLocker locker(context());
+
+    if (mode != channelCountMode()) {
+        exceptionState.throwDOMException(
+            NotSupportedError,
+            "Cannot change channelCountMode from \""
+                + channelCountMode()
+                + "\" to \""
+                + mode + "\"");
+    }
+}
+
 // ----------------------------------------------------------------
 
 OfflineAudioDestinationNode::OfflineAudioDestinationNode(BaseAudioContext& context, AudioBuffer* renderTarget)