Remove all blimp network code.

blimp/net/null_blimp_message_processor.cc

-// Copyright 2015 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 "blimp/net/null_blimp_message_processor.h"
-
-#include "blimp/common/logging.h"
-#include "blimp/net/common.h"
-
-namespace blimp {
-
-NullBlimpMessageProcessor::~NullBlimpMessageProcessor() {}
-
-void NullBlimpMessageProcessor::ProcessMessage(
-    std::unique_ptr<BlimpMessage> message,
-    const net::CompletionCallback& callback) {
-  DVLOG(2) << "Dropped message: " << *message;
-  if (!callback.is_null())
-    callback.Run(net::OK);
-}
-
-}  // namespace blimp