Fall back to shortcut A2HS when Phonesky is out of date or unavailable.

chrome/browser/android/webapk/chrome_webapk_host.cc

 // Copyright 2016 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/android/webapk/chrome_webapk_host.h"
 
+#include "base/android/jni_android.h"
+#include "base/bind.h"
 #include "chrome/browser/android/chrome_feature_list.h"
+#include "chrome/browser/android/webapk/webapk_install_service.h"
 #include "components/variations/variations_associated_data.h"
 #include "jni/ChromeWebApkHost_jni.h"
 
 namespace {
 
 // Variations flag to enable installing WebAPKs using Google Play.
 const char* kPlayInstall = "play_install";
 
+bool IsGooglePlayInstallAllowed() {
+  return variations::GetVariationParamValueByFeature(
+             chrome::android::kImprovedA2HS, kPlayInstall) == "true";
+}
+
 }  // anonymous namespace
 
 // static
 bool ChromeWebApkHost::Register(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 // static
 bool ChromeWebApkHost::AreWebApkEnabled() {
   JNIEnv* env = base::android::AttachCurrentThread();
   return Java_ChromeWebApkHost_areWebApkEnabled(env);
 }
 
 // static
 jboolean CanUseGooglePlayToInstallWebApk(
     JNIEnv* env,
     const base::android::JavaParamRef<jclass>& clazz) {
-  return variations::GetVariationParamValueByFeature(
-             chrome::android::kImprovedA2HS, kPlayInstall) == "true";
+  return IsGooglePlayInstallAllowed();
 }
+
+// static
+bool ChromeWebApkHost::CanUseGooglePlayToInstallWebApk() {
+  return IsGooglePlayInstallAllowed();
+}
+
+ChromeWebApkHost::ChromeWebApkHost() {
+  CreateJavaRef();
+}
+
+void ChromeWebApkHost::CanUseGooglePlayInstallApi(
+    const CanUseGooglePlayInstallApiCallback& callback) {
+  callback_ = callback;
+  Java_ChromeWebApkHost_canUseGooglePlayInstallApi(
+      base::android::AttachCurrentThread(), java_ref_);
+}
+
+void ChromeWebApkHost::OnCanUseGooglePlayInstallApi(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& obj,
+    jboolean is_available) {
+  callback_.Run(is_available);
+  delete this;
+}
+
+void ChromeWebApkHost::CreateJavaRef() {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  java_ref_.Reset(Java_ChromeWebApkHost_create(
+      env, reinterpret_cast<intptr_t>(this)));
+}
+
+ChromeWebApkHost::~ChromeWebApkHost() {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  Java_ChromeWebApkHost_destroy(env, java_ref_);
+  java_ref_.Reset();
+}