Enabled "top-chrome-md" flag to Linux.

chrome/browser/about_flags.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/about_flags.h"
 
 #include <iterator>
 #include <map>
 #include <set>
 #include <utility>
@@ skipping 801 matching lines @@
 #endif
     {"enable-scroll-prediction",
      IDS_FLAGS_ENABLE_SCROLL_PREDICTION_NAME,
      IDS_FLAGS_ENABLE_SCROLL_PREDICTION_DESCRIPTION,
      kOsDesktop,
      SINGLE_VALUE_TYPE(switches::kEnableScrollPrediction)},
 #if defined(ENABLE_TOPCHROME_MD)
     {"top-chrome-md",
      IDS_FLAGS_TOP_CHROME_MD,
      IDS_FLAGS_TOP_CHROME_MD_DESCRIPTION,
-     kOsWin | kOsCrOS,
+     kOsWin | kOsLinux | kOsCrOS,
      MULTI_VALUE_TYPE(kTopChromeMaterialDesignChoices)},
 #endif
     {"touch-events",
      IDS_TOUCH_EVENTS_NAME,
      IDS_TOUCH_EVENTS_DESCRIPTION,
      kOsDesktop,
      MULTI_VALUE_TYPE(kTouchEventsChoices)},
     {"disable-touch-adjustment",
      IDS_DISABLE_TOUCH_ADJUSTMENT_NAME,
      IDS_DISABLE_TOUCH_ADJUSTMENT_DESCRIPTION,
@@ skipping 1809 matching lines @@
 }
 
 const Experiment* GetExperiments(size_t* count) {
   *count = num_experiments;
   return experiments;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags