refactor: rename the atom directory to shell

shell/app/atom_library_main.mm

@@ -0,0 +1,38 @@
+// Copyright (c) 2013 GitHub, Inc.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#include "atom/app/atom_library_main.h"
+
+#include "atom/app/atom_main_delegate.h"
+#include "atom/app/node_main.h"
+#include "atom/common/atom_command_line.h"
+#include "atom/common/mac/main_application_bundle.h"
+#include "base/at_exit.h"
+#include "base/i18n/icu_util.h"
+#include "base/mac/bundle_locations.h"
+#include "base/mac/scoped_nsautorelease_pool.h"
+#include "content/public/app/content_main.h"
+
+int AtomMain(int argc, char* argv[]) {
+  atom::AtomMainDelegate delegate;
+  content::ContentMainParams params(&delegate);
+  params.argc = argc;
+  params.argv = const_cast<const char**>(argv);
+  atom::AtomCommandLine::Init(argc, argv);
+  return content::ContentMain(params);
+}
+
+#if BUILDFLAG(ENABLE_RUN_AS_NODE)
+int AtomInitializeICUandStartNode(int argc, char* argv[]) {
+  base::AtExitManager atexit_manager;
+  base::mac::ScopedNSAutoreleasePool pool;
+  base::mac::SetOverrideFrameworkBundlePath(
+      atom::MainApplicationBundlePath()
+          .Append("Contents")
+          .Append("Frameworks")
+          .Append(ELECTRON_PRODUCT_NAME " Framework.framework"));
+  base::i18n::InitializeICU();
+  return atom::NodeMain(argc, argv);
+}
+#endif