Remove all blimp engine code

blimp/engine/app/test_content_main_delegate.cc

Index: blimp/engine/app/test_content_main_delegate.cc
diff --git a/blimp/engine/app/test_content_main_delegate.cc b/blimp/engine/app/test_content_main_delegate.cc
deleted file mode 100644
index 77d05ab46f50eb073aea6ed6423c2b4d10d3c2cd..0000000000000000000000000000000000000000
--- a/blimp/engine/app/test_content_main_delegate.cc
+++ /dev/null
@@ -1,29 +0,0 @@
-// 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 "blimp/engine/app/test_content_main_delegate.h"
-
-namespace blimp {
-namespace engine {
-namespace {
-TestContentMainDelegate* g_content_main_delegate = nullptr;
-}  // namespace
-
-TestContentMainDelegate::TestContentMainDelegate() {
-  DCHECK(!g_content_main_delegate);
-  g_content_main_delegate = this;
-}
-
-TestContentMainDelegate::~TestContentMainDelegate() {
-  DCHECK_EQ(this, g_content_main_delegate);
-  g_content_main_delegate = nullptr;
-}
-
-// static
-TestContentMainDelegate* TestContentMainDelegate::GetInstance() {
-  return g_content_main_delegate;
-}
-
-}  // namespace engine
-}  // namespace blimp