Implement DOMQuad of geometry interfaces.

Source/core/dom/DOMQuad.idl

Index: Source/core/dom/DOMQuad.idl
diff --git a/Source/core/dom/DOMQuad.idl b/Source/core/dom/DOMQuad.idl
new file mode 100644
index 0000000000000000000000000000000000000000..c614eace3f1e06e4eb221dd3deec123ea6ff9c5b
--- /dev/null
+++ b/Source/core/dom/DOMQuad.idl
@@ -0,0 +1,17 @@
+// Copyright 2014 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.
+
+[
+    Constructor(Dictionary p1, Dictionary p2,
+                optional Dictionary p3, optional Dictionary p4),
+    Constructor(optional Dictionary rect),
+    GarbageCollected,
+    RuntimeEnabled=GeometryInterfaces,
+] interface DOMQuad {
+    readonly attribute DOMPoint p1;
+    readonly attribute DOMPoint p2;
+    readonly attribute DOMPoint p3;
+    readonly attribute DOMPoint p4;
+    readonly attribute DOMRectReadOnly bounds;
+};