Fall back to shortcut A2HS when Phonesky is out of date or unavailable.

chrome/browser/android/webapps/add_to_homescreen_manager.h

Index: chrome/browser/android/webapps/add_to_homescreen_manager.h
diff --git a/chrome/browser/android/webapps/add_to_homescreen_manager.h b/chrome/browser/android/webapps/add_to_homescreen_manager.h
index 1db089bab6780351e7a626add277ea21c667b5b4..b1e4a76bf55cfb1bd4b406d7d7daaa6d60d26832 100644
--- a/chrome/browser/android/webapps/add_to_homescreen_manager.h
+++ b/chrome/browser/android/webapps/add_to_homescreen_manager.h
@@ -8,6 +8,7 @@
 #include "base/android/jni_android.h"
 #include "base/android/scoped_java_ref.h"
 #include "base/macros.h"
+#include "chrome/browser/android/webapk/chrome_webapk_host.h"
 #include "chrome/browser/android/webapps/add_to_homescreen_data_fetcher.h"
 
 namespace content {
@@ -43,6 +44,23 @@ class AddToHomescreenManager : public AddToHomescreenDataFetcher::Observer {
  private:
   ~AddToHomescreenManager() override;
 
+  // Called by |Start()| which may check whether the WebAPK Install API is
+  // availabel asynchrously.
+  void StartImpl(content::WebContents* web_contents,
+                 bool check_webapk_compatible,
+                 bool can_use_webapk_install_flow);
+
+  // Checks whether the Google Play Install API is available when the Google
+  // Play install is allowed.
+  void CanUseGooglePlayInstallApi(
+      const ChromeWebApkHost::CanUseGooglePlayInstallApiCallback& callback);
+
+  // Called when the check of whether the Google Play Install API is available
+  // is done.
+  void OnCanUseGooglePlayInstallApi(content::WebContents* web_contents,
+                                    bool check_webapk_compatible,
+                                    bool isAvailable);
+
   // Shows alert to prompt user for name of home screen shortcut.
   void ShowDialog();