Convert Dictionary handling to RTCConfiguration IDL dictionary

third_party/WebKit/Source/modules/peerconnection/RTCIceServer.idl

Index: third_party/WebKit/Source/modules/peerconnection/RTCIceServer.idl
diff --git a/third_party/WebKit/Source/modules/peerconnection/RTCIceServer.idl b/third_party/WebKit/Source/modules/peerconnection/RTCIceServer.idl
new file mode 100644
index 0000000000000000000000000000000000000000..8a4941d144ba8712eb0a3461bafb9ecd324ba84b
--- /dev/null
+++ b/third_party/WebKit/Source/modules/peerconnection/RTCIceServer.idl
@@ -0,0 +1,14 @@
+// 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.
+
+// https://w3c.github.io/webrtc-pc/#rtciceserver-dictionary
+
+dictionary RTCIceServer {
+    // TODO(foolip): |urls| should be required and |url| is not in the spec.
+    (DOMString or sequence<DOMString>) urls;
+    DOMString url;
+    DOMString username;
+    DOMString credential;
+    // TODO(foolip): RTCIceCredentialType credentialType = "password";

[hta - Chromium, 2016/10/23 07:03:49]

Any reason not to add this now?

[foolip, 2016/10/23 08:58:56]

The question is what one would do with the "token" value, is that trivial to
support?

[hta - Chromium, 2016/10/23 16:39:02]

The correct handling given current support should be checking that the token is
"password", and taking the action prescribed in the spec for unknown values if
it's anything else.

[foolip, 2016/10/23 20:56:51]

Turns out that Gecko has credentialType in the dictionary,  but `new
RTCPeerConnection({ iceServers: [{ urls: "turn:turn.example.net", username:
"user", credential: "cred", credentialType: "token" }] })` logs
"RTCConfiguration TURN credentialType "token" is not yet implemented. Treating
as password. https://bugzil.la/1247616" in the console.

I don't think doing that is a good idea, there's then no way to later feature
detect when it's actually supported. Another way would be to have "password" as
the only RTCIceCredentialType enum entry, throwing TypeError for "token". Not
sure, an enum with just one value seems kind of pointless. WDYT?

+};