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

chrome/renderer/web_apps.cc

Index: chrome/renderer/web_apps.cc
diff --git a/chrome/renderer/web_apps.cc b/chrome/renderer/web_apps.cc
index 43c6056cce99f2d4db846a9c291f9c6c0ad72130..a5356139355e99e4b909a954fb2f959fcda316fc 100644
--- a/chrome/renderer/web_apps.cc
+++ b/chrome/renderer/web_apps.cc
@@ -152,7 +152,8 @@ void ParseWebAppFromWebDocument(WebFrame* frame,
       // "apple-touch-icon-precomposed".
 #if defined(OS_MACOSX)

[Lei Zhang, 2017/06/22 07:21:05]

Side question 2: This looks just like IsNewBookmarkAppsEnabled(). Did we ever
discuss moving that to chrome/common?

[benwells, 2017/06/22 07:34:10]

Good question. Currently IsNewBookmarkAppsEnabled is in
c/b/extensions/extension_util. We could create
c/common/extensions/extension_util, or do you have a better place to put it?

       bool bookmark_apps_enabled =

[Lei Zhang, 2017/06/22 07:21:05]

Side question 1: Can we move this out of the for-loop?

-          base::FeatureList::IsEnabled(features::kBookmarkApps);
+          base::FeatureList::IsEnabled(features::kBookmarkApps) ||
+          base::FeatureList::IsEnabled(features::kAppBanners);
 #else
       bool bookmark_apps_enabled = true;
 #endif