MD Settings: add a semi-functional System page

chrome/browser/extensions/api/settings_private/prefs_util.cc

 // Copyright 2015 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/extensions/api/settings_private/prefs_util.h"
 
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/chrome_extension_function.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 41 matching lines @@
 PrefsUtil::~PrefsUtil() {}
 
 #if defined(OS_CHROMEOS)
 using CrosSettings = chromeos::CrosSettings;
 #endif
 
 const PrefsUtil::TypedPrefMap& PrefsUtil::GetWhitelistedKeys() {
   static PrefsUtil::TypedPrefMap* s_whitelist = nullptr;
   if (s_whitelist)
     return *s_whitelist;
+  // TODO(dbeam): why aren't we using kPrefName from pref_names.h?
   s_whitelist = new PrefsUtil::TypedPrefMap();
   (*s_whitelist)["alternate_error_pages.enabled"] =
       settings_private::PrefType::PREF_TYPE_BOOLEAN;
   (*s_whitelist)["autofill.enabled"] =
       settings_private::PrefType::PREF_TYPE_BOOLEAN;
   (*s_whitelist)["bookmark_bar.show_on_all_tabs"] =
       settings_private::PrefType::PREF_TYPE_BOOLEAN;
   (*s_whitelist)["browser.show_home_button"] =
       settings_private::PrefType::PREF_TYPE_BOOLEAN;
 
@@ skipping 164 matching lines @@
       settings_private::PrefType::PREF_TYPE_NUMBER;
   (*s_whitelist)["settings.language.remap_caps_lock_key_to"] =
       settings_private::PrefType::PREF_TYPE_NUMBER;
   (*s_whitelist)["settings.language.remap_diamond_key_to"] =
       settings_private::PrefType::PREF_TYPE_NUMBER;
   (*s_whitelist)["settings.language.send_function_keys"] =
       settings_private::PrefType::PREF_TYPE_BOOLEAN;
 #else
   (*s_whitelist)["intl.accept_languages"] =
       settings_private::PrefType::PREF_TYPE_STRING;
+
+  // System settings.
+  (*s_whitelist)["background_mode.enabled"] =
+      settings_private::PrefType::PREF_TYPE_BOOLEAN;
+  (*s_whitelist)["hardware_acceleration_mode.enabled"] =
+      settings_private::PrefType::PREF_TYPE_BOOLEAN;
 #endif
 
 #if defined(GOOGLE_CHROME_BUILD)
   (*s_whitelist)["media_router.cloudservices.enabled"] =
       settings_private::PrefType::PREF_TYPE_BOOLEAN;
 #endif  // defined(GOOGLE_CHROME_BUILD)
 
   return *s_whitelist;
 }
 
@@ skipping 290 matching lines @@
 
 bool PrefsUtil::IsPrefSupervisorControlled(const std::string& pref_name) {
   if (pref_name != prefs::kBrowserGuestModeEnabled &&
       pref_name != prefs::kBrowserAddPersonEnabled) {
     return false;
   }
   return profile_->IsSupervised();
 }
 
 bool PrefsUtil::IsPrefUserModifiable(const std::string& pref_name) {
-  PrefService* pref_service = profile_->GetPrefs();
-  const PrefService::Preference* pref =
-      pref_service->FindPreference(pref_name.c_str());
-  return pref && pref->IsUserModifiable();
+  const PrefService::Preference* profile_pref =
+      profile_->GetPrefs()->FindPreference(pref_name);
+  if (profile_pref)
+    return profile_pref->IsUserModifiable();
+
+  const PrefService::Preference* local_state_pref =
+      g_browser_process->local_state()->FindPreference(pref_name);

[Dan Beam, 2016/03/08 07:13:21]

i guess this is the first local_state() pref we've ever try to set ...

+  if (local_state_pref)
+    return local_state_pref->IsUserModifiable();
+
+  return false;
 }
 
 PrefService* PrefsUtil::FindServiceForPref(const std::string& pref_name) {
   PrefService* user_prefs = profile_->GetPrefs();
 
   // Proxy is a peculiar case: on ChromeOS, settings exist in both user
   // prefs and local state, but chrome://settings should affect only user prefs.
   // Elsewhere the proxy settings are stored in local state.
   // See http://crbug.com/157147
 
@@ skipping 19 matching lines @@
 
 bool PrefsUtil::IsCrosSetting(const std::string& pref_name) {
 #if defined(OS_CHROMEOS)
   return CrosSettings::Get()->IsCrosSettings(pref_name);
 #else
   return false;
 #endif
 }
 
 }  // namespace extensions