net: Fix a regression that broke file uploading with http authentication

net/base/upload_data.cc

Index: net/base/upload_data.cc
diff --git a/net/base/upload_data.cc b/net/base/upload_data.cc
index 71d77ae807a102ae0b5edf64a7184269ddabf10e..b13e9091e8cb0051caeb26a516ba1cd806f600d0 100644
--- a/net/base/upload_data.cc
+++ b/net/base/upload_data.cc
@@ -114,6 +114,20 @@ uint64 UploadData::Element::BytesRemaining() {
   return GetContentLength() - offset_;
 }
 
+void UploadData::Element::ResetOffset() {
+  offset_ = 0;
+
+  // Delete the file stream if already opened, so we can reread the file from
+  // the beginning.
+  if (file_stream_) {
+    // Temporarily allow until fix: http://crbug.com/72001.
+    base::ThreadRestrictions::ScopedAllowIO allow_io;
+    file_stream_->CloseSync();
+    delete file_stream_;
+    file_stream_ = NULL;
+  }

[wtc, 2012/05/21 22:54:41]

As a performance optimization, we can leave file_stream_
open and simply seek to the beginning of the file:

  if (file_stream_) {
    // Temporarily allow until fix: http://crbug.com/72001.
    base::ThreadRestrictions::ScopedAllowIO allow_io;
    int64 offset = file_range_offset_? file_range_offset_ : 0;
    int64 rv = file->SeekSync(FROM_BEGIN, offset);
    if (rv < 0) {
       DLOG(WARNING) << "Failed to seek \"" << file_path_.value()
                    << "\" to offset: " << offset << " (" << rv
                    << ")";
      file_stream_->CloseSync();
      delete file_stream_;
      file_stream_ = NULL;
    }
  } 

[satorux1, 2012/05/21 23:14:40]

Thanks. I'm going to stick with my fix for now for easier merges to m19 and m20
branches. I'll revisit this at a later time.

+}
+
 FileStream* UploadData::Element::OpenFileStream() {
   scoped_ptr<FileStream> file(new FileStream(NULL));
   int64 rv = file->OpenSync(