Implement DOMPoint of geometry interfaces.

Source/core/dom/DOMPoint.idl

Index: Source/core/dom/DOMPoint.idl
diff --git a/Source/core/dom/DOMPoint.idl b/Source/core/dom/DOMPoint.idl
new file mode 100644
index 0000000000000000000000000000000000000000..aa2a0e4e6a8bf8e9ede3608ccd5690d472853175
--- /dev/null
+++ b/Source/core/dom/DOMPoint.idl
@@ -0,0 +1,25 @@
+// 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.
+
+// FIXME: Blink doesn't currently support dictionary definitions.
+// For now, we can use Dictionary interface. See http://crbug.com/321462.
+// dictionary DOMPointInit {
+//     unrestricted double x = 0;
+//     unrestricted double y = 0;
+//     unrestricted double z = 0;
+//     unrestricted double w = 1;
+// };
+
+[
+    Constructor(optional Dictionary point),
+    Constructor(unrestricted double x, unrestricted double y,
+                optional unrestricted double z = 0, optional unrestricted double w = 1),
+    RuntimeEnabled=GeometryInterfaces,
+] interface DOMPoint : DOMPointReadOnly {
+    // FIXME: Blink doesn't currently support inherit attribute.
+    inherit attribute unrestricted double x;
+    inherit attribute unrestricted double y;
+    inherit attribute unrestricted double z;
+    inherit attribute unrestricted double w;

[abarth-chromium, 2014/07/21 06:23:01]

What does "inhert" mean?  If we don't support it, we shouldn't have it in the
IDL file.

[zino, 2014/07/21 11:15:26]

Done.

+};