Remove PermissionContext factories

chrome/browser/media/midi_permission_context_factory.cc

-// 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.
-
-#include "chrome/browser/media/midi_permission_context_factory.h"
-
-#include "chrome/browser/media/midi_permission_context.h"
-#include "chrome/browser/profiles/incognito_helpers.h"
-#include "chrome/browser/profiles/profile.h"
-#include "components/keyed_service/content/browser_context_dependency_manager.h"
-
-// static
-MidiPermissionContext*
-MidiPermissionContextFactory::GetForProfile(Profile* profile) {
-  return static_cast<MidiPermissionContext*>(
-      GetInstance()->GetServiceForBrowserContext(profile, true));
-}
-
-// static
-MidiPermissionContextFactory*
-MidiPermissionContextFactory::GetInstance() {
-  return base::Singleton<MidiPermissionContextFactory>::get();
-}
-
-MidiPermissionContextFactory::MidiPermissionContextFactory()
-    : PermissionContextFactoryBase(
-          "MidiPermissionContext",
-          BrowserContextDependencyManager::GetInstance()) {
-}
-
-MidiPermissionContextFactory::~MidiPermissionContextFactory() {
-}
-
-KeyedService* MidiPermissionContextFactory::BuildServiceInstanceFor(
-    content::BrowserContext* profile) const {
-  return new MidiPermissionContext(static_cast<Profile*>(profile));
-}