*DRAFT* Move MediaDeviceIDSalt from chrome/ to components/ and use it in Android WebView.

components/media_device_id_salt/media_device_id_salt.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/media_device_id_salt.h"
+#include "components/media_device_id_salt/media_device_id_salt.h"
 
 #include "base/base64.h"
 #include "base/rand_util.h"
-#include "chrome/browser/profiles/profile_io_data.h"
-#include "chrome/common/pref_names.h"
 #include "components/prefs/pref_service.h"
 #include "content/public/browser/browser_thread.h"
 
 using content::BrowserThread;
 
+namespace media_device_id_salt {
+
+namespace prefs {
+
+const char kMediaDeviceIdSalt[] = "media.device_id_salt";
+
+}  // namespace prefs
+
 namespace {
 
 std::string CreateSalt() {
   std::string salt;
   base::Base64Encode(base::RandBytesAsString(16), &salt);
   DCHECK(!salt.empty());
   return salt;
 }
 
 }  // namespace
 
 MediaDeviceIDSalt::MediaDeviceIDSalt(PrefService* pref_service,
                                      bool incognito) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
   if (incognito) {
     incognito_salt_ = CreateSalt();
     return;
   }
 
   media_device_id_salt_.Init(prefs::kMediaDeviceIdSalt, pref_service);
   if (media_device_id_salt_.GetValue().empty())
     media_device_id_salt_.SetValue(CreateSalt());
 
   media_device_id_salt_.MoveToThread(
       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO));
 }
 
-MediaDeviceIDSalt::~MediaDeviceIDSalt() {
-}
+MediaDeviceIDSalt::~MediaDeviceIDSalt() {}
 
 void MediaDeviceIDSalt::ShutdownOnUIThread() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   if (incognito_salt_.empty())
     media_device_id_salt_.Destroy();
 }
 
 std::string MediaDeviceIDSalt::GetSalt() const {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   if (incognito_salt_.size())
     return incognito_salt_;
   return media_device_id_salt_.GetValue();
 }
 
 void MediaDeviceIDSalt::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* registry) {
   registry->RegisterStringPref(prefs::kMediaDeviceIdSalt, std::string());
 }
 
 void MediaDeviceIDSalt::Reset(PrefService* pref_service) {
-  pref_service->SetString(prefs::kMediaDeviceIdSalt,
-                          CreateSalt());
+  pref_service->SetString(prefs::kMediaDeviceIdSalt, CreateSalt());
 }
+
+}  // namespace media_device_id_salt