Replace --add-to-shelf flag with kAppBanners feature.

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 1967 matching lines @@
     {"enable-offline-previews", flag_descriptions::kEnableOfflinePreviewsName,
      flag_descriptions::kEnableOfflinePreviewsDescription, kOsAndroid,
      FEATURE_VALUE_TYPE(previews::features::kOfflinePreviews)},
     {"enable-client-lo-fi", flag_descriptions::kEnableClientLoFiName,
      flag_descriptions::kEnableClientLoFiDescription, kOsAndroid,
      FEATURE_VALUE_TYPE(previews::features::kClientLoFi)},
 #endif  // OS_ANDROID
     {"allow-insecure-localhost", flag_descriptions::kAllowInsecureLocalhostName,
      flag_descriptions::kAllowInsecureLocalhostDescription, kOsAll,
      SINGLE_VALUE_TYPE(switches::kAllowInsecureLocalhost)},
-    {"enable-add-to-shelf", flag_descriptions::kAddToShelfName,
-     flag_descriptions::kAddToShelfDescription, kOsDesktop,
-     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableAddToShelf,
-                               switches::kDisableAddToShelf)},
+#if !defined(OS_ANDROID)

[Matt Giuca, 2017/06/22 01:40:38]

Why !defined(OS_ANDROID)?

You already have kOsDesktop. Is the compile-time check necessary?

(The difference is, without the compile-time check, this will show up in
Android's flags as "not available on this platform" which is preferable to it
being confusingly missing.)

[benwells, 2017/06/22 05:57:48]

As discussed it's needed as the feature doesn't exist on Android, so otherwise
the FEATURE_VALUE_TYPE bit won't compile.

+    {"enable-app-banners", flag_descriptions::kAppBannersName,
+     flag_descriptions::kAppBannersDescription, kOsDesktop,
+     FEATURE_VALUE_TYPE(features::kAppBanners)},
+#endif
     {"bypass-app-banner-engagement-checks",
      flag_descriptions::kBypassAppBannerEngagementChecksName,
      flag_descriptions::kBypassAppBannerEngagementChecksDescription, kOsAll,
      SINGLE_VALUE_TYPE(switches::kBypassAppBannerEngagementChecks)},
     {"use-sync-sandbox", flag_descriptions::kSyncSandboxName,
      flag_descriptions::kSyncSandboxDescription, kOsAll,
      SINGLE_VALUE_TYPE_AND_VALUE(
          switches::kSyncServiceURL,
          "https://chrome-sync.sandbox.google.com/chrome-sync/alpha")},
 #if !defined(OS_ANDROID)
@@ skipping 1310 matching lines @@
 const base::HistogramBase::Sample kBadSwitchFormatHistogramId = 0;
 
 const FeatureEntry* GetFeatureEntries(size_t* count) {
   *count = arraysize(kFeatureEntries);
   return kFeatureEntries;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags