Enable Device Discovery by default on Linux, ChromeOS and Windows.

chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc

 // Copyright (c) 2012 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/chrome_web_ui_controller_factory.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/location.h"
 #include "base/message_loop/message_loop_proxy.h"
@@ skipping 214 matching lines @@
   if (url.host() == chrome::kChromeUICloudPrintResourcesHost)
     return &NewWebUI<ExternalWebDialogUI>;
   if (url.host() == chrome::kChromeUICloudPrintSetupHost)
     return &NewWebUI<WebDialogUI>;
   if (url.spec() == chrome::kChromeUIConstrainedHTMLTestURL)
     return &NewWebUI<ConstrainedWebDialogUI>;
   if (url.host() == chrome::kChromeUICrashesHost)
     return &NewWebUI<CrashesUI>;
 #if defined(ENABLE_MDNS)
   if (url.host() == chrome::kChromeUIDevicesFrameHost &&
-      CommandLine::ForCurrentProcess()->HasSwitch(
-            switches::kEnableDeviceDiscovery)) {
+      !CommandLine::ForCurrentProcess()->HasSwitch(
+           switches::kDisableDeviceDiscovery)) {
     return &NewWebUI<LocalDiscoveryUI>;
   }
 #endif
   if (url.host() == chrome::kChromeUIFlagsHost)
     return &NewWebUI<FlagsUI>;
   if (url.host() == chrome::kChromeUIHistoryFrameHost)
     return &NewWebUI<HistoryUI>;
   if (url.host() == chrome::kChromeUIInlineLoginHost)
     return &NewWebUI<InlineLoginUI>;
   if (url.host() == chrome::kChromeUIInstantHost)
@@ skipping 375 matching lines @@
   if (page_url.host() == chrome::kChromeUIPluginsHost)
     return PluginsUI::GetFaviconResourceBytes(scale_factor);
 
   // Android doesn't use the components pages.
   if (page_url.host() == chrome::kChromeUIComponentsHost)
     return ComponentsUI::GetFaviconResourceBytes(scale_factor);
 #endif
 
   return NULL;
 }