Blimp OAuth2 token retreival on application start up.

blimp/client/core/dummy_blimp_client_context.h

Index: blimp/client/core/dummy_blimp_client_context.h
diff --git a/blimp/client/core/dummy_blimp_client_context.h b/blimp/client/core/dummy_blimp_client_context.h
index 92f6e31356ae3c2d03aaa7c4ea42f52dd892716a..cdd6d9b9c91f20fdb730e59f460b9c35c835309b 100644
--- a/blimp/client/core/dummy_blimp_client_context.h
+++ b/blimp/client/core/dummy_blimp_client_context.h
@@ -21,6 +21,8 @@ class DummyBlimpClientContext : public BlimpClientContext {
   // BlimpClientContext implementation.
   void SetDelegate(BlimpClientContextDelegate* delegate) override;
   std::unique_ptr<BlimpContents> CreateBlimpContents() override;
+  void CreateAuthenticator(
+      std::unique_ptr<IdentityProvider> identity_provider) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DummyBlimpClientContext);