Remove PNaCL flag because it contains empty switch name.

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 <algorithm>
 #include <iterator>
 #include <map>
 #include <set>
@@ skipping 504 matching lines @@
     SINGLE_VALUE_TYPE(switches::kEnableNaClDebug)
   },
   {
     "nacl-debug-mask",  // FLAGS:RECORD_UMA
     IDS_FLAGS_NACL_DEBUG_MASK_NAME,
     IDS_FLAGS_NACL_DEBUG_MASK_DESCRIPTION,
     kOsDesktop,
     MULTI_VALUE_TYPE(kNaClDebugMaskChoices)
   },
   {
-    "disable-pnacl",  // FLAGS:RECORD_UMA
-    IDS_FLAGS_PNACL_NAME,
-    IDS_FLAGS_PNACL_DESCRIPTION,
-    kOsDesktop,
-    ENABLE_DISABLE_VALUE_TYPE("", switches::kDisablePnacl)
-  },
-  {
     "extension-apis",  // FLAGS:RECORD_UMA
     IDS_FLAGS_EXPERIMENTAL_EXTENSION_APIS_NAME,
     IDS_FLAGS_EXPERIMENTAL_EXTENSION_APIS_DESCRIPTION,
     kOsDesktop,
     SINGLE_VALUE_TYPE(extensions::switches::kEnableExperimentalExtensionApis)
   },
   {
     "extensions-on-chrome-urls",
     IDS_FLAGS_EXTENSIONS_ON_CHROME_URLS_NAME,
     IDS_FLAGS_EXTENSIONS_ON_CHROME_URLS_DESCRIPTION,
@@ skipping 1586 matching lines @@
 }
 
 const Experiment* GetExperiments(size_t* count) {
   *count = num_experiments;
   return experiments;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags