Make it possible to disable udev in linux

content/browser/gamepad/gamepad_platform_data_fetcher.h

 // 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.
 
 // Define the default data fetcher that GamepadProvider will use if none is
 // supplied. (GamepadPlatformDataFetcher).
 
 #ifndef CONTENT_BROWSER_GAMEPAD_GAMEPAD_PLATFORM_DATA_FETCHER_H_
 #define CONTENT_BROWSER_GAMEPAD_GAMEPAD_PLATFORM_DATA_FETCHER_H_
 
@@ skipping 12 matching lines @@
 namespace content {
 
 #if defined(OS_WIN)
 
 typedef GamepadPlatformDataFetcherWin GamepadPlatformDataFetcher;
 
 #elif defined(OS_MACOSX)
 
 typedef GamepadPlatformDataFetcherMac GamepadPlatformDataFetcher;
 
-#elif defined(OS_LINUX)
+#elif defined(OS_LINUX) && defined(USE_UDEV)
 
 typedef GamepadPlatformDataFetcherLinux GamepadPlatformDataFetcher;
 
 #else
 
 class GamepadDataFetcherEmpty : public GamepadDataFetcher {
  public:
   GamepadDataFetcherEmpty();
 
   virtual void GetGamepadData(blink::WebGamepads* pads,
                               bool devices_changed_hint) OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(GamepadDataFetcherEmpty);
 };
 typedef GamepadDataFetcherEmpty GamepadPlatformDataFetcher;
 
 #endif
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_GAMEPAD_GAMEPAD_PLATFORM_DATA_FETCHER_H_