Chrome talks to Play to install WebAPKs.

chrome/browser/android/webapk/webapk_installer.h

 // 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.
 
 #ifndef CHROME_BROWSER_ANDROID_WEBAPK_WEBAPK_INSTALLER_H_
 #define CHROME_BROWSER_ANDROID_WEBAPK_WEBAPK_INSTALLER_H_
 
 #include <jni.h>
 #include <memory>
 
@@ skipping 87 matching lines @@
       const base::android::ScopedJavaLocalRef<jstring>& java_file_path,
       const base::android::ScopedJavaLocalRef<jstring>& java_package_name);
 
   // Starts update using the downloaded WebAPK. Returns whether the updating
   // could be started. The updating may still fail if true is returned.
   // |file_path| is the file path that the WebAPK was downloaded to.
   virtual bool StartUpdateUsingDownloadedWebApk(
       JNIEnv* env,
       const base::android::ScopedJavaLocalRef<jstring>& java_file_path);
 
+  // Returns whether installing WebAPKs using Google Play is enabled.
+  virtual bool HasGooglePlayWebApkInstallDelegate();
+
   // Called when the request to install the WebAPK is sent to Google Play.
   void OnSuccess();
 
  private:
   enum TaskType {
     UNDEFINED,
     INSTALL,
     UPDATE,
   };
 
@@ skipping 18 matching lines @@
   // request the WebAPK server responds with the URL of the generated WebAPK.
   // |webapk| is the proto to send to the WebAPK server.
   void SendUpdateWebApkRequest(std::unique_ptr<webapk::WebApk> webapk_proto);
 
   // Sends a request to WebAPK server to create/update WebAPK. During a
   // successful request the WebAPK server responds with the URL of the generated
   // WebAPK.
   void SendRequest(std::unique_ptr<webapk::WebApk> request_proto,
                    const GURL& server_url);
 
+  // Called when the package name of the WebAPK is available and the install
+  // or update request is handled by Google Play.
+  void InstallOrUpdateWebApkFromGooglePlay(const std::string& package_name,
+                                           int version,
+                                           const std::string& token);
+
   // Called with the URL of generated WebAPK and the package name that the
   // WebAPK should be installed at.
   void OnGotWebApkDownloadUrl(const GURL& download_url,
                               const std::string& package_name);
 
   // Downloads the WebAPK from the given |download_url|.
   void DownloadWebApk(const base::FilePath& output_path,
                       const GURL& download_url,
                       bool retry_if_fails);
 
@@ skipping 80 matching lines @@
   // Points to the Java Object.
   base::android::ScopedJavaGlobalRef<jobject> java_ref_;
 
   // Used to get |weak_ptr_|.
   base::WeakPtrFactory<WebApkInstaller> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebApkInstaller);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_WEBAPK_WEBAPK_INSTALLER_H_