Add gamepad data fetcher for Linux

chrome/browser/about_flags.cc

 // Copyright (c) 2011 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/about_flags.h"
 
 #include <algorithm>
 #include <iterator>
 #include <map>
 #include <set>
@@ skipping 424 matching lines @@
     IDS_FLAGS_AURA_TRANSLUCENT_FRAMES_NAME,
     IDS_FLAGS_AURA_TRANSLUCENT_FRAMES_DESCRIPTION,
     kOsWin | kOsLinux | kOsCrOS,
     SINGLE_VALUE_TYPE(switches::kAuraTranslucentFrames)
   },
 #endif  // defined(USE_AURA)
   {
     "enable-gamepad",
     IDS_FLAGS_ENABLE_GAMEPAD_NAME,
     IDS_FLAGS_ENABLE_GAMEPAD_DESCRIPTION,
-    kOsMac | kOsWin,
+    kOsAll,
     SINGLE_VALUE_TYPE(switches::kEnableGamepad)
   },
 #if defined(USE_AURA)
   // TODO(jamescook): Enable this for all ChromeOS builds when we're sure
   // Aura laptop mode performance and feature set match traditional non-Aura
   // builds.
   {
     "aura-laptop-mode",
     IDS_FLAGS_AURA_LAPTOP_MODE_NAME,
     IDS_FLAGS_AURA_LAPTOP_MODE_DESCRIPTION,
@@ skipping 423 matching lines @@
 }
 
 const Experiment* GetExperiments(size_t* count) {
   *count = num_experiments;
   return experiments;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags