Add policy management for on-screen keyboard.

chrome/browser/chromeos/policy/proto/chrome_device_policy.proto

 // 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.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 package enterprise_management;
 
@@ skipping 424 matching lines @@
   // screen. If this policy is set, it controls the type of screen magnifier
   // that is enabled when the login screen is shown. Users can temporarily
   // override this setting by enabling or disabling the screen magnifier.
   // However, the user's choice is not persistent and the default is restored
   // whenever the login screen is shown anew or the user remains idle on the
   // login screen for a minute. If this policy is left unset, the screen
   // magnifier is disabled when the login screen is first shown. Users can
   // enable or disable the screen magnifier anytime and its status on the login
   // screen is persisted between users.
   optional ScreenMagnifierType login_screen_default_screen_magnifier_type = 4;
+
+  // Sets the default state of the on-screen keyboard accessibility feature on
+  // the login screen. If this policy is set to true, the on-screen keyboard
+  // will be enabled when the login screen is shown. If this policy is set to
+  // false, the on-screen keyboard will be disabled when the login screen is
+  // shown. Users can temporarily override this setting by enabling or disabling
+  // the on-screen keyboard. However, the user's choice is not persistent and
+  // the default is restored whenever the login screen is shown anew or the user
+  // remains idle on the login screen for a minute. If this policy is left
+  // unset, the on-screen keyboard is disabled when the login screen is first
+  // shown. Users can enable or disable the on-screen keyboard anytime and its
+  // status on the login screen is persisted between users.
+  optional bool login_screen_default_virtual_keyboard_enabled = 5;
 }
 
 message SupervisedUsersSettingsProto {
   // Defines whether supervised users can be created on the device.
   optional bool supervised_users_enabled = 1;
 }
 
 message LoginScreenPowerManagementProto {
   // Configures power management on the login screen. The policy should be
   // specified as a string that expresses the individual settings in JSON
@@ skipping 121 matching lines @@
   optional StartUpFlagsProto start_up_flags = 23;
   optional UptimeLimitProto uptime_limit = 24;
   optional VariationsParameterProto variations_parameter = 25;
   optional AttestationSettingsProto attestation_settings = 26;
   optional AccessibilitySettingsProto accessibility_settings = 27;
   optional SupervisedUsersSettingsProto supervised_users_settings = 28;
   optional LoginScreenPowerManagementProto login_screen_power_management = 29;
   optional SystemUse24HourClockProto use_24hour_clock = 30;
   optional AutoCleanupSettigsProto auto_clean_up_settings = 31;
 }