Patch #1 of multiple. Add webauth .mojom and initial usage of makeCredential.

components/webauth/authenticator.mojom

+// 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.
+
+[JavaPackage="org.chromium.webauth.mojom"]
+module webauth.mojom;
+
+struct ScopedCredentialInfo {
+  array<uint8> clientData;

[dcheng, 2017/02/28 07:25:56]

Nit: hacker_case instead of camelCase for variable names in mojom

[kpaulhamus, 2017/03/01 01:56:34]

Done.

+  array<uint8> attestation;
+};
+
+struct RelyingPartyAccount {
+    string rpDisplayName;

[dcheng, 2017/02/28 07:25:56]

Nit: 2 space indent.

[kpaulhamus, 2017/03/01 01:56:34]

Done.

+    string displayName;
+    string id;
+    string name;
+    string imageURL;
+};
+
+struct ScopedCredentialParameters {
+  ScopedCredentialType type;
+  //TODO add AlgorithmIdentifier algorithm;

[dcheng, 2017/02/28 07:25:56]

Nit: TODO comment format is
// TODO(username or https://crbug.com/number): Do that.

[kpaulhamus, 2017/03/01 01:56:34]

Done.

+};
+
+struct ScopedCredentialOptions {
+  int32 timeoutSeconds;
+  string rpId;
+  array<ScopedCredentialDescriptor> excludeList;
+  //TODO add Extensions
+};
+
+enum ScopedCredentialType {
+    SCOPEDCRED,
+};
+
+struct ScopedCredentialDescriptor {
+  ScopedCredentialType type;
+  array<uint8> id;
+  array<Transport> transports;
+};
+
+enum Transport {
+    USB,
+    NFC,
+    BLE,
+};
+
+interface Authenticator {
+  makeCredential(RelyingPartyAccount accountInformation,

[dcheng, 2017/02/28 07:25:56]

Nit: even though this is in Blink, methods should be named with UpperCamelCase.
The Blink rename is happening soon, and will fix the inconsistencies in Blink.

[kpaulhamus, 2017/03/01 01:56:34]

Done.

+                 array<ScopedCredentialParameters> cryptoParameters,
+                 array<uint8> attestationChallenge,
+                 ScopedCredentialOptions? options)
+      => (array<ScopedCredentialInfo> scopedCredentials);
+};