Blimp OAuth2 token retreival on application start up.

blimp/client/core/blimp_client_context_impl.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 "blimp/client/core/blimp_client_context_impl.h"
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/threading/sequenced_task_runner_handle.h"
@@ skipping 54 matching lines @@
   // registered.
   io_thread_task_runner_->PostTask(
       FROM_HERE, base::Bind(&ClientNetworkComponents::Initialize,
                             base::Unretained(net_components_.get())));
 }
 
 BlimpClientContextImpl::~BlimpClientContextImpl() {
   io_thread_task_runner_->DeleteSoon(FROM_HERE, net_components_.release());
 }
 
+void BlimpClientContextImpl::Connect() {

[nyquist, 2016/08/12 05:47:04]

Nit: You see if it makes sense to order these functions like in the header?

[xingliu, 2016/08/12 21:11:18]

Done.

+  // Lazy initialization of IdentitySource.
+  if (!identity_source_) {
+    DCHECK(delegate_);
+    identity_source_ =
+        base::MakeUnique<IdentitySource>(delegate_->CreateIdentityProvider());
+    identity_source_->SetDelegate(delegate_);
+  }
+
+  // Start Blimp authentication flow.
+  identity_source_->Connect();
+}
+
 void BlimpClientContextImpl::SetDelegate(BlimpClientContextDelegate* delegate) {
   delegate_ = delegate;
 }
 
 std::unique_ptr<BlimpContents> BlimpClientContextImpl::CreateBlimpContents() {
   std::unique_ptr<BlimpContents> blimp_contents =
       blimp_contents_manager_->CreateBlimpContents();
   delegate_->AttachBlimpContentsHelpers(blimp_contents.get());
   return blimp_contents;
 }
@@ skipping 34 matching lines @@
   }
 
   io_thread_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&ClientNetworkComponents::ConnectWithAssignment,
                  base::Unretained(net_components_.get()), assignment));
 }
 
 }  // namespace client
 }  // namespace blimp