Mojo EDK: Remove unused var on windows

mojo/edk/system/channel_win.cc

 // Copyright 2016 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 "mojo/edk/system/channel.h"
 
 #include <windows.h>
 
 #include <algorithm>
 #include <deque>
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/synchronization/lock.h"
 #include "base/task_runner.h"
 #include "mojo/edk/embedder/platform_handle_vector.h"
 
 namespace mojo {
 namespace edk {
 
 namespace {
 
-const size_t kMaxBatchReadCapacity = 256 * 1024;
-
 // A view over a Channel::Message object. The write queue uses these since
 // large messages may need to be sent in chunks.
 class MessageView {
  public:
   // Owns |message|. |offset| indexes the first unsent byte in the message.
   MessageView(Channel::MessagePtr message, size_t offset)
       : message_(std::move(message)),
         offset_(offset) {
     DCHECK_GT(message_->data_num_bytes(), offset_);
   }
@@ skipping 258 matching lines @@
 // static
 scoped_refptr<Channel> Channel::Create(
     Delegate* delegate,
     ScopedPlatformHandle platform_handle,
     scoped_refptr<base::TaskRunner> io_task_runner) {
   return new ChannelWin(delegate, std::move(platform_handle), io_task_runner);
 }
 
 }  // namespace edk
 }  // namespace mojo