Make chrome://flags control whether the WebAPK feature is on

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 2000 matching lines @@
      IDS_FLAGS_QUICK_UNLOCK_PIN_DESCRIPTION, kOsCrOS,
      FEATURE_VALUE_TYPE(features::kQuickUnlockPin)},
 #endif  // OS_CHROMEOS
     {"browser-task-scheduler", IDS_FLAGS_BROWSER_TASK_SCHEDULER_NAME,
      IDS_FLAGS_BROWSER_TASK_SCHEDULER_DESCRIPTION, kOsAll,
      ENABLE_DISABLE_VALUE_TYPE(switches::kEnableBrowserTaskScheduler,
                                switches::kDisableBrowserTaskScheduler)},
 #if defined(OS_ANDROID)
     {"enable-improved-a2hs", IDS_FLAGS_ENABLE_WEBAPK,
      IDS_FLAGS_ENABLE_WEBAPK_DESCRIPTION, kOsAndroid,
-     SINGLE_VALUE_TYPE(switches::kEnableWebApk)},
+     FEATURE_VALUE_TYPE(chrome::android::kImprovedA2HS)},
     {"no-credit-card-abort", IDS_FLAGS_NO_CREDIT_CARD_ABORT,
      IDS_FLAGS_NO_CREDIT_CARD_ABORT_DESCRIPTION, kOsAndroid,
      FEATURE_VALUE_TYPE(chrome::android::kNoCreditCardAbort)},
 #endif  // OS_ANDROID
     {"enable-feature-policy", IDS_FLAGS_FEATURE_POLICY_NAME,
      IDS_FLAGS_FEATURE_POLICY_DESCRIPTION, kOsAll,
      FEATURE_VALUE_TYPE(features::kFeaturePolicy)},
 #if defined(OS_CHROMEOS)
     {"enable-emoji-handwriting-voice-on-ime-menu",
      IDS_FLAGS_ENABLE_EHV_INPUT_NAME, IDS_FLAGS_ENABLE_EHV_INPUT_DESCRIPTION,
@@ skipping 298 matching lines @@
 const base::HistogramBase::Sample kBadSwitchFormatHistogramId = 0;
 
 const FeatureEntry* GetFeatureEntries(size_t* count) {
   *count = arraysize(kFeatureEntries);
   return kFeatureEntries;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags