Enable Native CUPS printing on Chrome OS.

chrome/browser/ui/webui/print_preview/printer_backend_proxy_chromeos.cc

 // Copyright 2016 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/ui/webui/print_preview/printer_backend_proxy.h"
 
 #include <memory>
 #include <vector>
 
 #include "base/bind_helpers.h"
@@ skipping 116 matching lines @@
                                      base::Bind(cb, ""));
   };
 
   void EnumeratePrinters(const EnumeratePrintersCallback& cb) override {
     // PrintersManager is not thread safe and must be called from the UI
     // thread.
     DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
     PrinterList printer_list;
 
-    if (base::CommandLine::ForCurrentProcess()->HasSwitch(
-            switches::kEnableNativeCups)) {
+    if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
+            switches::kDisableNativeCups)) {
       AddPrintersToList(prefs_->GetPrinters(), &printer_list);
       AddPrintersToList(prefs_->GetRecommendedPrinters(), &printer_list);
     }
 
     content::BrowserThread::PostTask(content::BrowserThread::UI, FROM_HERE,
                                      base::Bind(cb, printer_list));
   };
 
   void ConfigurePrinterAndFetchCapabilities(
       const std::string& printer_name,
@@ skipping 24 matching lines @@
 };
 
 }  // namespace
 
 std::unique_ptr<PrinterBackendProxy> PrinterBackendProxy::Create(
     Profile* profile) {
   return base::MakeUnique<PrinterBackendProxyChromeos>(profile);
 }
 
 }  // namespace printing