Fall back to shortcut A2HS when Phonesky is out of date or unavailable.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 "chrome/browser/android/chrome_feature_list.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";
 
 }  // anonymous namespace
 
 // static
 bool ChromeWebApkHost::Register(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 // static
-bool ChromeWebApkHost::AreWebApkEnabled() {
+bool ChromeWebApkHost::CanInstallWebApk() {
   JNIEnv* env = base::android::AttachCurrentThread();
-  return Java_ChromeWebApkHost_areWebApkEnabled(env);
+  return Java_ChromeWebApkHost_canInstallWebApk(env);
 }
 
 // static
 jboolean CanUseGooglePlayToInstallWebApk(
     JNIEnv* env,
     const base::android::JavaParamRef<jclass>& clazz) {
   return variations::GetVariationParamValueByFeature(
              chrome::android::kImprovedA2HS, kPlayInstall) == "true";
 }
+
+// static
+jboolean CanInstallFromUnknownSources(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jclass>& clazz) {
+  return base::FeatureList::GetInstance()->IsFeatureOverriddenFromCommandLine(
+             chrome::android::kImprovedA2HS.name,
+             base::FeatureList::OVERRIDE_ENABLE_FEATURE);
+}