Restrict number of BlimpContents to [0, 1]

blimp/client/public/blimp_client_context.h

 // 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.
 
 #ifndef BLIMP_CLIENT_PUBLIC_BLIMP_CLIENT_CONTEXT_H_
 #define BLIMP_CLIENT_PUBLIC_BLIMP_CLIENT_CONTEXT_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 34 matching lines @@
   // The |file_thread_task_runner| must be the task runner to use for file
   // operations.
   static BlimpClientContext* Create(
       scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner,
       scoped_refptr<base::SingleThreadTaskRunner> file_thread_task_runner);
 
   // The delegate provides all the required functionality from the embedder.
   virtual void SetDelegate(BlimpClientContextDelegate* delegate) = 0;
 
   // Creates a new BlimpContents.
+  // Currently we want to have a single BlimpContents. If there is an existing

[David Trainor- moved to gerrit, 2016/08/30 23:31:12]

Add the same TODO.

[Menglin, 2016/08/31 00:13:02]

Done.

+  // contents, return nullptr.
   virtual std::unique_ptr<BlimpContents> CreateBlimpContents() = 0;
 
   // Start authentication flow and connection to engine.
   virtual void Connect() = 0;
 
  protected:
   BlimpClientContext() = default;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(BlimpClientContext);
 };
 
 }  // namespace client
 }  // namespace blimp
 
 #endif  // BLIMP_CLIENT_PUBLIC_BLIMP_CLIENT_CONTEXT_H_