Add enable-service-worker-navigation-preload flag in chrome://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 1109 matching lines @@
     {"enable-navigation-tracing", IDS_FLAGS_ENABLE_NAVIGATION_TRACING,
      IDS_FLAGS_ENABLE_NAVIGATION_TRACING_DESCRIPTION, kOsAll,
      SINGLE_VALUE_TYPE(switches::kEnableNavigationTracing)},
     {"trace-upload-url", IDS_FLAGS_TRACE_UPLOAD_URL,
      IDS_FLAGS_TRACE_UPLOAD_URL_DESCRIPTION, kOsAll,
      MULTI_VALUE_TYPE(kTraceUploadURL)},
     {"enable-stale-while-revalidate",
      IDS_FLAGS_ENABLE_STALE_WHILE_REVALIDATE_NAME,
      IDS_FLAGS_ENABLE_STALE_WHILE_REVALIDATE_DESCRIPTION, kOsAll,
      FEATURE_VALUE_TYPE(features::kStaleWhileRevalidate)},
+    {"enable-service-worker-navigation-preload",
+     IDS_FLAGS_SERVICE_WORKER_NAVIGATION_PRELOAD_NAME,
+     IDS_FLAGS_SERVICE_WORKER_NAVIGATION_PRELOAD_DESCRIPTION, kOsAll,
+     FEATURE_VALUE_TYPE(features::kServiceWorkerNavigationPreload)},
     {"enable-suggestions-with-substring-match",
      IDS_FLAGS_SUGGESTIONS_WITH_SUB_STRING_MATCH_NAME,
      IDS_FLAGS_SUGGESTIONS_WITH_SUB_STRING_MATCH_DESCRIPTION, kOsAll,
      SINGLE_VALUE_TYPE(
          autofill::switches::kEnableSuggestionsWithSubstringMatch)},
     {"enable-speculative-launch-service-worker",
      IDS_FLAGS_SPECULATIVE_LAUNCH_SERVICE_WORKER_NAME,
      IDS_FLAGS_SPECULATIVE_LAUNCH_SERVICE_WORKER_DESCRIPTION, kOsAll,
      FEATURE_VALUE_TYPE(features::kSpeculativeLaunchServiceWorker)},
     {"enable-supervised-user-managed-bookmarks-folder",
@@ skipping 1271 matching lines @@
 const base::HistogramBase::Sample kBadSwitchFormatHistogramId = 0;
 
 const FeatureEntry* GetFeatureEntries(size_t* count) {
   *count = arraysize(kFeatureEntries);
   return kFeatureEntries;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags