[PresentationAPI] Plumbing send(Blob) from PresentationSession IDL to platform/.

Source/modules/presentation/PresentationSession.h

 // Copyright 2014 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 PresentationSession_h
 #define PresentationSession_h
 
 #include "core/events/EventTarget.h"
+#include "core/fileapi/Blob.h"
+#include "core/fileapi/FileError.h"
 #include "core/frame/DOMWindowProperty.h"
 #include "public/platform/modules/presentation/WebPresentationSessionClient.h"
 #include "wtf/text/WTFString.h"
 
 namespace WTF {
 class AtomicString;
 } // namespace WTF
 
 namespace blink {
 
@@ skipping 18 matching lines @@
     virtual ExecutionContext* executionContext() const override;
 
     DECLARE_VIRTUAL_TRACE();
 
     const String id() const { return m_id; }
     const WTF::AtomicString& state() const;
 
     void send(const String& message, ExceptionState&);
     void send(PassRefPtr<DOMArrayBuffer> data, ExceptionState&);
     void send(PassRefPtr<DOMArrayBufferView> data, ExceptionState&);
+    void send(Blob* data, ExceptionState&);
     void close();
 
     DEFINE_ATTRIBUTE_EVENT_LISTENER(message);
     DEFINE_ATTRIBUTE_EVENT_LISTENER(statechange);
 
     // Returns true if and only if the WebPresentationSessionClient represents this session.
     bool matches(WebPresentationSessionClient*) const;
 
     // Notifies the session about its state change.
     void didChangeState(WebPresentationSessionState);
 
     // Notifies the session about new text message.
     void didReceiveTextMessage(const String& message);
 
 private:
+    // Blob data items are queued and sent after loading asynchronously.
+    struct Message {
+        Message(PassRefPtr<BlobDataHandle> blobDataHandle)
+            : blobDataHandle(blobDataHandle)
+        {
+        }
+
+        RefPtr<BlobDataHandle> blobDataHandle;
+        // TODO(): Check the need for queuing String and ArrayBuffer also.

[mlamouri (slow - plz ping), 2015/05/19 13:08:55]

TODO(<handle>), plz

[mark a. foltz, 2015/05/20 15:40:04]

What does this mean?  String and ArrayBuffer should be available immediately as
their data content is part of the script value.

[USE s.singapati at gmail.com, 2015/05/21 19:49:55]

Updated comments. Currently String and ArrayBuffer data is sent immediately to
the client, but Blob data is loaded as array buffer and then sent. This makes
message sending order incorrect. If we go with current approach (loading Blobs
here), then we probably need to queue String & ArrayBuffer also to preserve the
order.

+    };
+
     PresentationSession(LocalFrame*, const String& id, const String& url);
 
     // Returns the |PresentationController| object associated with the frame
     // |Presentation| corresponds to. Can return |nullptr| if the frame is
     // detached from the document.
     PresentationController* presentationController();
 
     // Common send method for both ArrayBufferView and ArrayBuffer.
     void sendInternal(const uint8_t* data, size_t, ExceptionState&);
 
+    void handleMessageQueue();
+
+    class BlobLoader;

[mark a. foltz, 2015/05/20 15:40:04]

Forward declarations should go immediately after private (like typedefs):

http://google-styleguide.googlecode.com/svn/trunk/cppguide.html#Declaration_O...

[mark a. foltz, 2015/05/20 15:40:04]

Should this be class BlobLoader {
  void didFinishLoadingBlob()
  void didFailLoadingBlob()
}

Otherwise I don't follow how the methods below are related to the BlobLoader
forward declaration.

[USE s.singapati at gmail.com, 2015/05/21 19:49:54]

Done. Updated comment. didFinishLoadingBlob() & didFailLoadingBlob() are invoked
from BlobLoader.

[USE s.singapati at gmail.com, 2015/05/21 19:49:55]

Done.

+    // Methods for BlobLoader.

[mlamouri (slow - plz ping), 2015/05/19 13:08:55]

s/Methods/Callbacks/

[USE s.singapati at gmail.com, 2015/05/21 19:49:55]

Done.

+    void didFinishLoadingBlob(PassRefPtr<DOMArrayBuffer>);
+    void didFailLoadingBlob(FileError::ErrorCode);
+
     String m_id;
     String m_url;
     WebPresentationSessionState m_state;
+
+    // For Blob data handling.
+    Member<BlobLoader> m_blobLoader;
+    Deque<OwnPtr<Message>> m_messages;
 };
 
 } // namespace blink
 
 #endif // PresentationSession_h