[fsp] Remove length from the OnWriteFileOperation().

chrome/browser/chromeos/file_system_provider/operations/write_file.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/chromeos/file_system_provider/operations/write_file.h"
 
 #include "base/debug/trace_event.h"
 #include "base/values.h"
 #include "chrome/common/extensions/api/file_system_provider.h"
 #include "chrome/common/extensions/api/file_system_provider_internal.h"
@@ skipping 22 matching lines @@
 
 bool WriteFile::Execute(int request_id) {
   TRACE_EVENT0("file_system_provider", "WriteFile::Execute");
 
   if (!file_system_info_.writable())
     return false;
 
   scoped_ptr<base::DictionaryValue> values(new base::DictionaryValue);
   values->SetInteger("openRequestId", file_handle_);
   values->SetDouble("offset", offset_);
-  values->SetInteger("length", length_);
+  // Length is not passed directly since it can be accessed via data.byteLength.
 
   DCHECK(buffer_.get());
   values->Set(
       "data",
       base::BinaryValue::CreateWithCopiedBuffer(buffer_->data(), length_));
 
   return SendEvent(
       request_id,
       extensions::api::file_system_provider::OnWriteFileRequested::kEventName,
       values.Pass());
 }
 
 void WriteFile::OnSuccess(int /* request_id */,
                           scoped_ptr<RequestValue> /* result */,
                           bool /* has_more */) {
   TRACE_EVENT0("file_system_provider", "WriteFile::OnSuccess");
   callback_.Run(base::File::FILE_OK);
 }
 
 void WriteFile::OnError(int /* request_id */,
                         scoped_ptr<RequestValue> /* result */,
                         base::File::Error error) {
   TRACE_EVENT0("file_system_provider", "WriteFile::OnError");
   callback_.Run(error);
 }
 
 }  // namespace operations
 }  // namespace file_system_provider
 }  // namespace chromeos