Fall back to shortcut A2HS when Phonesky is out of date or unavailable.

chrome/browser/android/webapps/add_to_homescreen_manager.cc

Index: chrome/browser/android/webapps/add_to_homescreen_manager.cc
diff --git a/chrome/browser/android/webapps/add_to_homescreen_manager.cc b/chrome/browser/android/webapps/add_to_homescreen_manager.cc
index 3608e943e34200d435da7aae84e1ee3567502880..25be3a55bd4d91f3831187a85153c5935cbae4f1 100644
--- a/chrome/browser/android/webapps/add_to_homescreen_manager.cc
+++ b/chrome/browser/android/webapps/add_to_homescreen_manager.cc
@@ -79,17 +79,35 @@ void AddToHomescreenManager::Start(content::WebContents* web_contents) {
   if (ChromeWebApkHost::AreWebApkEnabled() &&
       InstallableManager::IsContentSecure(web_contents)) {
     check_webapk_compatible = true;
-  } else {
-    ShowDialog();
+    if (ChromeWebApkHost::CanUseGooglePlayToInstallWebApk()) {
+      // It is possible that the Google Play Install API isn't available when
+      // Google Play install is enabled. In that case, we fallback to classic
+      // add-to-homescreen shortcut flow.
+      ChromeWebApkHost::CanUseGooglePlayInstallApiCallback callback
+          = base::Bind(&AddToHomescreenManager::OnCanUseGooglePlayInstallApi,
+                       base::Unretained(this),
+                       web_contents, check_webapk_compatible);
+      ChromeWebApkHost::CanUseGooglePlayInstallApi(callback);
+      return;
+    }
   }
 
+  StartImpl(web_contents, check_webapk_compatible, true);
+}
+
+void AddToHomescreenManager::StartImpl(content::WebContents* web_contents,
+                                       bool check_webapk_compatible,
+                                       bool can_use_webapk_install_flow) {
+  if (!check_webapk_compatible)
+    ShowDialog();
+
   data_fetcher_ = new AddToHomescreenDataFetcher(
       web_contents, ShortcutHelper::GetIdealHomescreenIconSizeInPx(),
       ShortcutHelper::GetMinimumHomescreenIconSizeInPx(),
       ShortcutHelper::GetIdealSplashImageSizeInPx(),
       ShortcutHelper::GetMinimumSplashImageSizeInPx(),
       ShortcutHelper::GetIdealBadgeIconSizeInPx(),
-      check_webapk_compatible, this);
+      check_webapk_compatible, can_use_webapk_install_flow, this);
 }
 
 AddToHomescreenManager::~AddToHomescreenManager() {
@@ -99,6 +117,13 @@ AddToHomescreenManager::~AddToHomescreenManager() {
   }
 }
 
+void AddToHomescreenManager::OnCanUseGooglePlayInstallApi(
+    content::WebContents* web_contents,
+    bool check_webapk_compatible,
+    bool isAvailable) {
+  StartImpl(web_contents, check_webapk_compatible, isAvailable);
+}
+
 void AddToHomescreenManager::ShowDialog() {
   JNIEnv* env = base::android::AttachCurrentThread();
   Java_AddToHomescreenManager_showDialog(env, java_ref_);
@@ -194,7 +219,8 @@ void AddToHomescreenManager::CreateInfoBarForWebApk(const ShortcutInfo& info,
   banners::AppBannerInfoBarDelegateAndroid::Create(
       data_fetcher_->web_contents(), nullptr, info.user_title,
       base::MakeUnique<ShortcutInfo>(info), base::MakeUnique<SkBitmap>(icon),
-      -1 /* event_request_id */, webapk::INSTALL_SOURCE_MENU);
+      -1 /* event_request_id */, true /* can_use_webapk_install_flow */,
+      webapk::INSTALL_SOURCE_MENU);
 }
 
 SkBitmap AddToHomescreenManager::FinalizeLauncherIconInBackground(