Implement app banner info bars on desktop.

chrome/browser/ui/tab_helpers.cc

Index: chrome/browser/ui/tab_helpers.cc
diff --git a/chrome/browser/ui/tab_helpers.cc b/chrome/browser/ui/tab_helpers.cc
index 495f01074f744e324faa8eeadd23e8530b616aad..edc3cf7d6e31f1caf4cc0188e37d3ee5733e481e 100644
--- a/chrome/browser/ui/tab_helpers.cc
+++ b/chrome/browser/ui/tab_helpers.cc
@@ -5,6 +5,7 @@
 #include "chrome/browser/ui/tab_helpers.h"
 
 #include "base/command_line.h"
+#include "chrome/browser/banners/app_banner_manager_desktop.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/content_settings/chrome_content_settings_client.h"
 #include "chrome/browser/content_settings/tab_specific_content_settings.h"
@@ -201,6 +202,13 @@ void TabHelpers::AttachTabHelpers(WebContents* web_contents) {
   MetroPinTabHelper::CreateForWebContents(web_contents);
 #endif
 
+#if !defined(OS_ANDROID)
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableAddToShelf)) {
+    banners::AppBannerManagerDesktop::CreateForWebContents(web_contents);
+  }
+#endif
+
   // --- Feature tab helpers behind flags ---
 
 #if defined(ENABLE_CAPTIVE_PORTAL_DETECTION)