[Extensions] Remove principalsPrivate API

chrome/common/extensions/api/schemas.gypi

 # Copyright 2014 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.
 
 {
   'sources': [
     '<@(schema_files)',
   ],
   'variables': {
     'main_schema_files': [
@@ skipping 79 matching lines @@
       'windows.json',
     ],
     'main_schema_include_rules': [
       'extensions/common/api:extensions::api::%(namespace)s',
     ],
     'main_non_compiled_schema_files': [
       'browsing_data.json',
       'extension.json',
       'idltest.idl',
       'music_manager_private.idl',
-      'principals_private.idl',
       'top_sites.json',
     ],
 
     # ChromeOS-specific schemas.
     'chromeos_schema_files': [
       'cast_devices_private.idl',
       'certificate_provider.idl',
       'certificate_provider_internal.idl',
       'echo_private.json',
       'enterprise_device_attributes.idl',
@@ skipping 91 matching lines @@
           '<@(webrtc_schema_files)',
         ],
       }],
     ],
     'cc_dir': 'chrome/common/extensions/api',
     'root_namespace': 'extensions::api::%(namespace)s',
     'bundle_name': 'Chrome',
     'impl_dir_': 'chrome/browser/extensions/api',
   },
 }