Remove ability to switch to pre-MD UI from about:flags.

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 344 matching lines @@
   { IDS_FLAGS_EXTENSION_CONTENT_VERIFICATION_ENFORCE,
     switches::kExtensionContentVerification,
     switches::kExtensionContentVerificationEnforce },
   { IDS_FLAGS_EXTENSION_CONTENT_VERIFICATION_ENFORCE_STRICT,
     switches::kExtensionContentVerification,
     switches::kExtensionContentVerificationEnforceStrict },
 };
 
 const FeatureEntry::Choice kTopChromeMaterialDesignChoices[] = {
   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
-  { IDS_FLAGS_TOP_CHROME_MD_NON_MATERIAL,
-    switches::kTopChromeMD,
-    switches::kTopChromeMDNonMaterial },
   { IDS_FLAGS_TOP_CHROME_MD_MATERIAL,
     switches::kTopChromeMD,
     switches::kTopChromeMDMaterial },
   { IDS_FLAGS_TOP_CHROME_MD_MATERIAL_HYBRID,
     switches::kTopChromeMD,
     switches::kTopChromeMDMaterialHybrid },
 };
 
 #if defined(OS_CHROMEOS)
 
@@ skipping 1890 matching lines @@
 const base::HistogramBase::Sample kBadSwitchFormatHistogramId = 0;
 
 const FeatureEntry* GetFeatureEntries(size_t* count) {
   *count = arraysize(kFeatureEntries);
   return kFeatureEntries;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags