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

chrome/browser/flag_descriptions.cc

 // Copyright 2017 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/flag_descriptions.h"
 
 namespace flag_descriptions {
 
 const char kBrowserSideNavigationName[] = "Enable browser side navigation";
 
@@ skipping 246 matching lines @@
 
 const char kSecondaryUiMdDescription[] =
     "Extends the --top-chrome-md setting to secondary UI (bubbles, dialogs, "
     "etc.). On Mac, this enables MacViews, which uses toolkit-views for "
     "native browser dialogs.";
 
 const char kScrollPredictionDescription[] =
     "Predicts the finger's future position during scrolls allowing time to "
     "render the frame before the finger is there.";
 
-const char kAddToShelfName[] = "Add to shelf";
+const char kAppBannersName[] = "App Banners";
 
-const char kAddToShelfDescription[] =
-    "Enable the display of add to shelf banners, which prompt a user to add "
-    "a web app to their shelf, or other platform-specific equivalent.";
+const char kAppBannersDescription[] =
+    "Enable the display of Progressive Web App banners, which prompt a user to "
+    "add a web app to their shelf, or other platform-specific equivalent.";
 
 const char kBypassAppBannerEngagementChecksName[] =
     "Bypass user engagement checks";
 
 const char kBypassAppBannerEngagementChecksDescription[] =
     "Bypasses user engagement checks for displaying app banners, such as "
     "requiring that users have visited the site before and that the banner "
     "hasn't been shown recently. This allows developers to test that other "
     "eligibility requirements for showing app banners, such as having a "
     "manifest, are met.";
@@ skipping 2994 matching lines @@
     "in non-sticky mode (do not change work area in non-sticky mode).";
 
 const char kUiDevToolsName[] = "Enable native UI inspection";
 const char kUiDevToolsDescription[] =
     "Enables inspection of native UI elements. For local inspection use "
     "chrome://inspect#other";
 
 #endif  // defined(OS_CHROMEOS)
 
 }  // namespace flag_descriptions