[cros] Add checkbox for toggling data roaming setting.

chrome/browser/chromeos/cros_settings_names.cc

Index: chrome/browser/chromeos/cros_settings_names.cc
diff --git a/chrome/browser/chromeos/cros_settings_names.cc b/chrome/browser/chromeos/cros_settings_names.cc
index 556eb68f3eac6a53c4c14199989ff498f0baaa57..46e5ee5e48d2e7ce54c2c215696fb3b27551ca6f 100644
--- a/chrome/browser/chromeos/cros_settings_names.cc
+++ b/chrome/browser/chromeos/cros_settings_names.cc
@@ -8,12 +8,16 @@ namespace chromeos {
 
 const char kCrosSettingsPrefix[] = "cros.";
 
+// All cros.accounts.* settings are stored in SignedSettings.
 const char kAccountsPrefAllowGuest[] = "cros.accounts.allowBWSI";
 const char kAccountsPrefAllowNewUser[] = "cros.accounts.allowGuest";
 const char kAccountsPrefShowUserNamesOnSignIn[]
     = "cros.accounts.showUserNamesOnSignIn";
 const char kAccountsPrefUsers[] = "cros.accounts.users";
 
+// All cros.signed.* settings are stored in SignedSettings.
+const char kSignedDataRoamingEnabled[] = "cros.signed.data_roaming_enabled";
+
 const char kSystemTimezone[] = "cros.system.timezone";
 
 const char kDeviceOwner[] = "cros.device.owner";