Add policy to use system default printer

chrome/browser/policy/configuration_policy_handler_list_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/policy/configuration_policy_handler_list_factory.h"
 
 #include <limits.h>
 #include <stddef.h>
 
 #include <utility>
@@ skipping 600 matching lines @@
 
 #if !defined(OS_CHROMEOS) && !defined(OS_ANDROID)
   { key::kNativeMessagingUserLevelHosts,
     extensions::pref_names::kNativeMessagingUserLevelHosts,
     base::Value::Type::BOOLEAN },
   { key::kBrowserAddPersonEnabled,
     prefs::kBrowserAddPersonEnabled,
     base::Value::Type::BOOLEAN },
 #endif  // !defined(OS_CHROMEOS) && !defined(OS_ANDROID)
 
+#if !defined(OS_CHROMEOS) && !defined(OS_ANDROID) && !defined(OS_IOS)

[Lei Zhang, 2017/06/19 23:41:40]

I'm not 100% sure, but I thought there's no iOS code in chrome/ ?

+eugenebut to give a definitive answer.

[Eugene But (OOO till 7-30), 2017/06/20 00:53:57]

I confirm that there is no iOS code in chrome/

[Lei Zhang, 2017/06/20 00:56:25]

Thanks! Should we in a separate CL, clear out the OS_IOS usage in chrome/, and
maybe add a presubmit check?

[rbpotter, 2017/06/20 02:58:25]

Removed all newly added IOS checks.

+  { key::kPrintPreviewUseSystemDefaultPrinter,
+    prefs::kPrintPreviewUseSystemDefaultPrinter,
+    base::Value::Type::BOOLEAN },
+#endif  // !defined(OS_CHROMEOS) && !defined(OS_ANDROID) && !defined(OS_IOS)
+
   { key::kForceBrowserSignin,
     prefs::kForceBrowserSignin,
     base::Value::Type::BOOLEAN },
 
 #if defined(OS_WIN)
   { key::kWelcomePageOnOSUpgradeEnabled,
     prefs::kWelcomePageOnOSUpgradeEnabled,
     base::Value::Type::BOOLEAN },
 #endif  // OS_WIN
 
@@ skipping 413 matching lines @@
 #endif  // defined(OS_CHROMEOS)
 
 #if BUILDFLAG(ENABLE_PLUGINS)
   handlers->AddHandler(base::MakeUnique<PluginPolicyHandler>());
 #endif  // BUILDFLAG(ENABLE_PLUGINS)
 
   return handlers;
 }
 
 }  // namespace policy