arc: Pass auth token from Chrome to ARC instance.

components/arc/auth/arc_auth_fetcher.cc

Index: components/arc/auth/arc_auth_fetcher.cc
diff --git a/components/arc/auth/arc_auth_fetcher.cc b/components/arc/auth/arc_auth_fetcher.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e67333fe430000af346a84b0ff91162bc82e24fb
--- /dev/null
+++ b/components/arc/auth/arc_auth_fetcher.cc
@@ -0,0 +1,59 @@
+// 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.
+
+#include "components/arc/auth/arc_auth_fetcher.h"
+
+#include "base/strings/stringprintf.h"
+#include "google_apis/gaia/gaia_constants.h"
+#include "google_apis/gaia/gaia_urls.h"
+
+namespace arc {
+
+namespace {
+
+const char kGMSCoreClientId[] =
+    "1070009224336-sdh77n7uot3oc99ais00jmuft6sk2fg9.apps.googleusercontent.com";
+
+}  // namespace
+
+ArcAuthFetcher::ArcAuthFetcher(net::URLRequestContextGetter* getter,
+                               Delegate* delegate)
+    : delegate_(delegate), auth_fetcher_(this, std::string(), getter) {
+  FetchAuthCode();
+}
+
+// static
+GURL ArcAuthFetcher::CreateURL() {
+  std::string query_string =
+      base::StringPrintf("?scope=%s&client_id=%s",
+                         GaiaConstants::kOAuth1LoginScope, kGMSCoreClientId);
+  return GaiaUrls::GetInstance()->client_login_to_oauth2_url().Resolve(
+      query_string);
+}
+
+void ArcAuthFetcher::FetchAuthCode() {
+  DCHECK(!auth_fetcher_.HasPendingFetch());
+  auth_fetcher_.StartCookieForOAuthLoginTokenExchange(
+      false, /* fetch_token_from_auth_code */
+      std::string(),    /* session_index */
+      kGMSCoreClientId, std::string() /* device_id */);
+}
+
+void ArcAuthFetcher::OnClientOAuthCode(const std::string& auth_code) {
+  DCHECK(!auth_fetcher_.HasPendingFetch());
+  delegate_->OnAuthCodeFetched(auth_code);
+}
+
+void ArcAuthFetcher::OnClientOAuthFailure(const GoogleServiceAuthError& error) {
+  // UNEXPECTED_SERVICE_RESPONSE indicates no cookies in response, but request
+  // is completed successfully.
+  if (error.state() == GoogleServiceAuthError::UNEXPECTED_SERVICE_RESPONSE) {
+    delegate_->OnAuthCodeNeedUI();
+  } else {
+    VLOG(2) << "ARC Auth request failed: " << error.ToString() << ".";
+    delegate_->OnAuthCodeFailed();
+  }
+}
+
+}  // namespace arc