Blimp OAuth2 token retreival on application start up.

blimp/client/public/blimp_client_context.h

Index: blimp/client/public/blimp_client_context.h
diff --git a/blimp/client/public/blimp_client_context.h b/blimp/client/public/blimp_client_context.h
index e43e73905044e01ee4bf6870122362d24c6e84b8..c04a7dc1d6e070f83321ee042b0582fde27670be 100644
--- a/blimp/client/public/blimp_client_context.h
+++ b/blimp/client/public/blimp_client_context.h
@@ -12,6 +12,7 @@
 #include "blimp/client/public/blimp_client_context_delegate.h"
 #include "blimp/client/public/contents/blimp_contents.h"
 #include "components/keyed_service/core/keyed_service.h"
+#include "google_apis/gaia/identity_provider.h"
 
 #if defined(OS_ANDROID)
 #include "base/android/jni_android.h"
@@ -50,6 +51,10 @@ class BlimpClientContext : public KeyedService {
   // Creates a new BlimpContents.
   virtual std::unique_ptr<BlimpContents> CreateBlimpContents() = 0;
 
+  // Create OAuth2 token authenticator.
+  virtual void CreateAuthenticator(

[nyquist, 2016/08/10 01:20:34]

Could you move this to the BlimpClientContextDelegate instead? Something like:
std::unique_ptr<IdentityProvider> CreateIdentityProvider()?

[xingliu, 2016/08/10 21:03:15]

Done. This is great idea.

+      std::unique_ptr<IdentityProvider> identity_provider) = 0;
+
  protected:
   BlimpClientContext() = default;