[Presentation API] (alternative) 1-UA: send message between controller and receiver page

content/renderer/presentation/presentation_connection_client.h

 // Copyright 2015 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 CONTENT_RENDERER_PRESENTATION_PRESENTATION_SESSION_CLIENT_H_
 #define CONTENT_RENDERER_PRESENTATION_PRESENTATION_SESSION_CLIENT_H_
 
 #include "base/compiler_specific.h"
 #include "content/common/content_export.h"
+#include "content/renderer/presentation/renderer_presentation_connection.h"
 #include "third_party/WebKit/public/platform/modules/presentation/WebPresentationConnectionClient.h"
 #include "third_party/WebKit/public/platform/modules/presentation/presentation.mojom.h"
 #include "url/gurl.h"
 
 namespace content {
 
 // PresentationConnectionClient is passed to the Blink layer if presentation
 // session has been created successfully. Owned by the callback.
 class CONTENT_EXPORT PresentationConnectionClient
     : public NON_EXPORTED_BASE(blink::WebPresentationConnectionClient) {
  public:
   explicit PresentationConnectionClient(
       blink::mojom::PresentationSessionInfoPtr session_info);
   explicit PresentationConnectionClient(const GURL& url,
                                         const mojo::String& id);
+  explicit PresentationConnectionClient(

[mark a. foltz, 2016/10/08 00:33:42]

No need for explicit on 2-argument ctor

[imcheng, 2016/10/12 02:22:54]

Could you also please document what the different constructors are for?

Specifically, could you clarify whether PresentationConnectionClient is supposed
to take ownership of |proxy| (until getOrCreateProxy is called). What happens if
getOrCreateProxy is never called, or more than once?

[zhaobin, 2016/10/12 02:27:33]

Done.

[zhaobin, 2016/10/13 02:33:52]

Done.

+      blink::mojom::PresentationSessionInfoPtr session_info,
+      blink::WebPresentationConnectionProxy* proxy);
   ~PresentationConnectionClient() override;
 
   // WebPresentationConnectionClient implementation.
   blink::WebURL getUrl() override;
   blink::WebString getId() override;
+  blink::WebPresentationConnectionProxy* getOrCreateProxy() override;
 
  private:
   blink::WebURL url_;
   blink::WebString id_;
+  blink::WebPresentationConnectionProxy* proxy_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PRESENTATION_PRESENTATION_SESSION_CLIENT_H_