Turn components/crash into a layered component.

components/crash/app/breakpad_mac_stubs.mm

-// Copyright 2013 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.
-
-#import "components/crash/app/breakpad_mac.h"
-
-#import <Foundation/Foundation.h>
-
-// Stubbed out versions of breakpad integration functions so we can compile
-// without linking in Breakpad.
-
-namespace breakpad {
-
-bool IsCrashReporterEnabled() {
-  return false;
-}
-
-void InitCrashProcessInfo(const std::string& process_type_switch) {
-}
-
-void InitCrashReporter(const std::string& process_type) {
-}
-
-}  // namespace breakpad