Remove all blimp engine code

blimp/engine/app/blimp_main.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 "base/command_line.h"
-#include "blimp/engine/app/blimp_content_main_delegate.h"
-#include "blimp/engine/app/blimp_engine_config.h"
-#include "content/public/app/content_main.h"
-
-
-int main(int argc, const char** argv) {
-  base::CommandLine::Init(argc, argv);
-  blimp::engine::SetCommandLineDefaults(base::CommandLine::ForCurrentProcess());
-
-  blimp::engine::BlimpContentMainDelegate delegate;
-  content::ContentMainParams params(&delegate);
-  params.argc = argc;
-  params.argv = argv;
-  return content::ContentMain(params);
-}