Blimp OAuth2 token retreival on application start up.

chrome/browser/android/blimp/chrome_blimp_client_context_delegate.cc

 // 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 "chrome/browser/android/blimp/chrome_blimp_client_context_delegate.h"
 
+#include "base/memory/ptr_util.h"
 #include "blimp/client/public/blimp_client_context.h"
 #include "blimp/client/public/blimp_client_context_delegate.h"
 #include "blimp/client/public/contents/blimp_contents.h"
 #include "chrome/browser/android/blimp/blimp_client_context_factory.h"
 #include "chrome/browser/android/blimp/blimp_contents_profile_attachment.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/signin/profile_oauth2_token_service_factory.h"
+#include "chrome/browser/signin/signin_manager_factory.h"
+#include "components/signin/core/browser/profile_identity_provider.h"
+#include "components/signin/core/browser/signin_manager.h"
 
 ChromeBlimpClientContextDelegate::ChromeBlimpClientContextDelegate(
     Profile* profile)
     : profile_(profile),
       blimp_client_context_(
           BlimpClientContextFactory::GetForBrowserContext(profile)) {
   blimp_client_context_->SetDelegate(this);
 }
 
 ChromeBlimpClientContextDelegate::~ChromeBlimpClientContextDelegate() {
   blimp_client_context_->SetDelegate(nullptr);
 }
 
 void ChromeBlimpClientContextDelegate::AttachBlimpContentsHelpers(
     blimp::client::BlimpContents* blimp_contents) {
   AttachProfileToBlimpContents(blimp_contents, profile_);
 }
 
 void ChromeBlimpClientContextDelegate::OnAssignmentConnectionAttempted(
     blimp::client::AssignmentRequestResult result,
     const blimp::client::Assignment& assignment) {}
+
+std::unique_ptr<IdentityProvider>
+ChromeBlimpClientContextDelegate::CreateIdentityProvider() {
+  return base::WrapUnique<IdentityProvider>(new ProfileIdentityProvider(
+      SigninManagerFactory::GetForProfile(profile_),
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile_),
+      base::Closure()));
+}
+
+void ChromeBlimpClientContextDelegate::OnAuthenticationError(
+    BlimpClientContextDelegate::AuthError error) {
+  switch (error) {
+    case AuthError::NOT_SIGNED_IN:
+      // User need to signed in first, on Android it's handled in Java layer
+      // before the connection.
+      VLOG(1) << "User is not signed in before connection to Blimp.";
+      break;
+    case AuthError::OAUTH_TOKEN_FAIL:
+      // TODO(xingliu): Alert the user in UI.
+      // There is an known issue that ongoing request can be cancelled when
+      // Android layer updates the refresh token.
+      break;
+    default:
+      VLOG(1) << "Unknown Blimp error.";

[nyquist, 2016/08/16 18:38:06]

I don't think this should ever happen, so maybe LOG(WARNING) ?

[xingliu, 2016/08/17 00:32:24]

Done.

+  }
+}