Move the exception logic to the AudioNode creator

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

Index: third_party/WebKit/Source/modules/webaudio/WaveShaperNode.cpp
diff --git a/third_party/WebKit/Source/modules/webaudio/WaveShaperNode.cpp b/third_party/WebKit/Source/modules/webaudio/WaveShaperNode.cpp
index 783e2cfd9d975a89ee66f6996a58a0952d021c30..6247608772b04eb3787fcc6a249c5428de6a2b28 100644
--- a/third_party/WebKit/Source/modules/webaudio/WaveShaperNode.cpp
+++ b/third_party/WebKit/Source/modules/webaudio/WaveShaperNode.cpp
@@ -39,6 +39,18 @@ WaveShaperNode::WaveShaperNode(AbstractAudioContext& context)
     handler().initialize();
 }
 
+WaveShaperNode* WaveShaperNode::create(AbstractAudioContext& context, ExceptionState& exceptionState)
+{
+    DCHECK(isMainThread());
+
+    if (context.isContextClosed()) {
+        context.throwExceptionForClosedState(exceptionState);
+        return nullptr;
+    }
+
+    return new WaveShaperNode(context);
+}
+
 WaveShaperProcessor* WaveShaperNode::getWaveShaperProcessor() const
 {
     return static_cast<WaveShaperProcessor*>(static_cast<AudioBasicProcessorHandler&>(handler()).processor());