Add constructors for WebAudio nodes

third_party/WebKit/Source/modules/webaudio/IIRFilterOptions.idl

Index: third_party/WebKit/Source/modules/webaudio/IIRFilterOptions.idl
diff --git a/third_party/WebKit/Source/modules/webaudio/IIRFilterOptions.idl b/third_party/WebKit/Source/modules/webaudio/IIRFilterOptions.idl
new file mode 100644
index 0000000000000000000000000000000000000000..8e66304654290589f9899a51a847e75770138080
--- /dev/null
+++ b/third_party/WebKit/Source/modules/webaudio/IIRFilterOptions.idl
@@ -0,0 +1,9 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// See https://webaudio.github.io/web-audio-api/#iirfilteroptions
+dictionary IIRFilterOptions : AudioNodeOptions {
+    sequence<double> feedforward;
+    sequence<double> feedback;
+};