[chrome.displaySource] Consolidate media pipeline initialization.

extensions/renderer/api/display_source/wifi_display/wifi_display_media_pipeline.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 EXTENSIONS_RENDERER_API_DISPLAY_SOURCE_WIFI_DISPLAY_WIFI_DISPLAY_MEDIA_PIPELINE_H_
 #define EXTENSIONS_RENDERER_API_DISPLAY_SOURCE_WIFI_DISPLAY_WIFI_DISPLAY_MEDIA_PIPELINE_H_
 
 #include <memory>
 #include <string>
 #include <vector>
@@ skipping 29 matching lines @@
   static std::unique_ptr<WiFiDisplayMediaPipeline> Create(
       wds::SessionType type,
       const WiFiDisplayVideoEncoder::InitParameters& video_parameters,
       const wds::AudioCodec& audio_codec,
       const std::string& sink_ip_address,
       const std::pair<int, int>& sink_rtp_ports,
       const RegisterMediaServiceCallback& service_callback,
       const ErrorCallback& error_callback);
   ~WiFiDisplayMediaPipeline();
   // Note: to be called only once.
-  void Initialize(
-      const InitCompletionCallback& callback);
+  void Initialize(const InitCompletionCallback& callback);
 
   void InsertRawVideoFrame(
       const scoped_refptr<media::VideoFrame>& video_frame,
       base::TimeTicks reference_time);
 
   void RequestIDRPicture();
 
  private:
+  using InitStepCompletionCallback = InitCompletionCallback;
+  enum InitializationStep : unsigned;
+
   WiFiDisplayMediaPipeline(
       wds::SessionType type,
       const WiFiDisplayVideoEncoder::InitParameters& video_parameters,
       const wds::AudioCodec& audio_codec,
       const std::string& sink_ip_address,
       const std::pair<int, int>& sink_rtp_ports,
       const RegisterMediaServiceCallback& service_callback,
       const ErrorCallback& error_callback);
 
-  void CreateVideoEncoder();
   void CreateMediaPacketizer();
+  void OnInitialize(const InitCompletionCallback& callback,
+                    InitializationStep current_step,
+                    bool success);
   void OnVideoEncoderCreated(
+      const InitStepCompletionCallback& callback,
       scoped_refptr<WiFiDisplayVideoEncoder> video_encoder);
-  void OnMediaServiceRegistered();
+  void OnMediaServiceRegistered(const InitCompletionCallback& callback);
 
   void OnEncodedVideoFrame(const WiFiDisplayEncodedFrame& frame);
 
   bool OnPacketizedMediaDatagramPacket(
      WiFiDisplayMediaDatagramPacket media_datagram_packet);
 
   scoped_refptr<WiFiDisplayVideoEncoder> video_encoder_;
   std::unique_ptr<WiFiDisplayMediaPacketizer> packetizer_;
 
   wds::SessionType type_;
   WiFiDisplayVideoEncoder::InitParameters video_parameters_;
   wds::AudioCodec audio_codec_;
   std::string sink_ip_address_;
   std::pair<int, int> sink_rtp_ports_;
 
   RegisterMediaServiceCallback service_callback_;
   ErrorCallback error_callback_;
-  InitCompletionCallback init_completion_callback_;
   WiFiDisplayMediaServicePtr media_service_;
 
   base::WeakPtrFactory<WiFiDisplayMediaPipeline> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WiFiDisplayMediaPipeline);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_API_DISPLAY_SOURCE_WIFI_DISPLAY_WIFI_DISPLAY_MEDIA_PIPELINE_H_