net: Make UploadDataStream::Read() asynchronous

net/base/upload_bytes_element_reader.h

Index: net/base/upload_bytes_element_reader.h
diff --git a/net/base/upload_bytes_element_reader.h b/net/base/upload_bytes_element_reader.h
index 1467ed767c68a8d58d7f858bab6f8fb357bb3d21..5edb11c70a55a90690f186579b730d09ccc1e132 100644
--- a/net/base/upload_bytes_element_reader.h
+++ b/net/base/upload_bytes_element_reader.h
@@ -21,8 +21,11 @@ class NET_EXPORT_PRIVATE UploadBytesElementReader : public UploadElementReader {
   virtual int InitSync() OVERRIDE;
   virtual uint64 GetContentLength() const OVERRIDE;
   virtual uint64 BytesRemaining() const OVERRIDE;
-  virtual int ReadSync(char* buf, int buf_length) OVERRIDE;
   virtual bool IsInMemory() const OVERRIDE;
+  virtual int Read(IOBuffer* buf,
+                   int buf_length,
+                   const CompletionCallback& callback) OVERRIDE;
+  virtual int ReadSync(IOBuffer* buf, int buf_length) OVERRIDE;
 
  private:
   const char* bytes_;