[PresentationAPI] on-session-message handler for ArrayBuffer and Blob messages.

content/renderer/presentation/presentation_dispatcher.cc

Index: content/renderer/presentation/presentation_dispatcher.cc
diff --git a/content/renderer/presentation/presentation_dispatcher.cc b/content/renderer/presentation/presentation_dispatcher.cc
index 8100c03b94ed8b117aa243379d37bd18328ef2eb..8e0dd1d16550c36498924c276de1da5a9ed4db3d 100644
--- a/content/renderer/presentation/presentation_dispatcher.cc
+++ b/content/renderer/presentation/presentation_dispatcher.cc
@@ -369,14 +369,35 @@ void PresentationDispatcher::OnSessionMessagesReceived(
     return;
 
   for (size_t i = 0; i < messages.size(); ++i) {
-    if (messages[i]->type ==
-        presentation::PresentationMessageType::PRESENTATION_MESSAGE_TYPE_TEXT) {
-      controller_->didReceiveSessionTextMessage(
-          new PresentationSessionClient(messages[i]->presentation_url,
-                                        messages[i]->presentation_id),
-          blink::WebString::fromUTF8(messages[i]->message));
-    } else {
-      // TODO(haibinlu): handle binary message
+    scoped_ptr<PresentationSessionClient> session_client(
+        new PresentationSessionClient(messages[i]->presentation_url,

[mark a. foltz, 2015/06/29 22:21:28]

It appears that this ctor will copy the contents of presentation_url and
presentation_id into a blink::WebString each time through this loop.  Then look
up the PresentationSession to dispatch the event in Presentation.cpp.

This is not ideal from an efficiency point of view, but it's likely that there
will only be one message in the queue, and there is only one active session per
frame.  As this can be optimized later, can you add a NOTE that passing batches
of messages to the Blink layer would be more efficient?

+                                      messages[i]->presentation_id));
+    switch (messages[i]->type) {
+      case presentation::PresentationMessageType::
+          PRESENTATION_MESSAGE_TYPE_TEXT: {
+        controller_->didReceiveSessionTextMessage(
+            session_client.release(),
+            blink::WebString::fromUTF8(messages[i]->message));
+        break;
+      }
+      case presentation::PresentationMessageType::
+          PRESENTATION_MESSAGE_TYPE_ARRAY_BUFFER: {
+        controller_->didReceiveSessionArrayBufferMessage(
+            session_client.release(), &(messages[i]->data.front()),
+            messages[i]->data.size());
+        break;
+      }
+      case presentation::PresentationMessageType::
+          PRESENTATION_MESSAGE_TYPE_BLOB: {
+        controller_->didReceiveSessionBlobMessage(session_client.release(),
+                                                  &(messages[i]->data.front()),
+                                                  messages[i]->data.size());
+        break;
+      }
+      default: {
+        NOTREACHED();
+        break;
+      }
     }
   }