Add WebAuthn bindings and client interface.

third_party/WebKit/Source/modules/webauth/RelyingPartyAccount.idl

Index: third_party/WebKit/Source/modules/webauth/RelyingPartyAccount.idl
diff --git a/third_party/WebKit/Source/modules/webauth/RelyingPartyAccount.idl b/third_party/WebKit/Source/modules/webauth/RelyingPartyAccount.idl
new file mode 100644
index 0000000000000000000000000000000000000000..fbf6f8033ade77fcc58cd6bdfcd2be7b1d680cfa
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+++ b/third_party/WebKit/Source/modules/webauth/RelyingPartyAccount.idl
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+// 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/webauthn/#dictdef-account
+
+dictionary RelyingPartyAccount {
+    required DOMString rpDisplayName;
+    required DOMString displayName;
+    required DOMString id;
+    DOMString name;
+    DOMString imageURL;
+};