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

public/platform/modules/presentation/WebPresentationClient.h

Index: public/platform/modules/presentation/WebPresentationClient.h
diff --git a/public/platform/modules/presentation/WebPresentationClient.h b/public/platform/modules/presentation/WebPresentationClient.h
index 15e4d6e15845395d0046f36c3c35d3e8381763bf..a60ce32b0c16c19db37dcb634e5bff7ff6b34f7d 100644
--- a/public/platform/modules/presentation/WebPresentationClient.h
+++ b/public/platform/modules/presentation/WebPresentationClient.h
@@ -44,8 +44,17 @@ public:
     virtual void sendString(const WebString& presentationUrl, const WebString& presentationId, const WebString& message) = 0;
 
     // Called when the frame requests to send ArrayBuffer/View data to an existing session.
+    // Embedder copies the |data| and the ownership is not transferred.
     virtual void sendArrayBuffer(const WebString& presentationUrl, const WebString& presentationId, const uint8_t* data, size_t length) = 0;
 
+    // Called when the frame requests to send Blob data to an existing session.
+    // Embedder copies the |data| and the ownership is not transferred.
+    virtual void sendBlobData(const WebString& presentationUrl, const WebString& presentationId, const uint8_t* data, size_t length)
+    {
+        // TODO(s.singapati): Make this method pure virtual once Chromium has the implementation.
+        BLINK_ASSERT_NOT_REACHED();
+    }
+
     // Called when the frame requests to close an existing session.
     virtual void closeSession(const WebString& url, const WebString& presentationId) = 0;
 };