net: Make UploadDataStream::Read() asynchronous

net/base/upload_data.h

Index: net/base/upload_data.h
diff --git a/net/base/upload_data.h b/net/base/upload_data.h
index b35263cc23352b83637ce3c1a9eb4df6a49c8e6a..d4314257593cc27c2f99fa8f481926846aa2bff9 100644
--- a/net/base/upload_data.h
+++ b/net/base/upload_data.h
@@ -60,7 +60,7 @@ class NET_EXPORT UploadData
   void set_chunk_callback(ChunkCallback* callback);
 
   // Initializes the object to send chunks of upload data over time rather
-  // than all at once.
+  // than all at once. Only bytes can be appended for chunked data.

[mmenke, 2012/10/15 19:54:45]

Think this statement is too weak, since other functions that modify elements
don't work for initializing chunk encoded streams, either.  Suggest just
"Chunked data may only contain bytes, not files."

[hashimoto, 2012/10/16 11:52:20]

Done.

   void set_is_chunked(bool set) { is_chunked_ = set; }
   bool is_chunked() const { return is_chunked_; }