customtabs: Extract a redirect endpoint, and maybe connect to it.

chrome/android/java/src/org/chromium/chrome/browser/init/ChromeBrowserInitializer.java

 // Copyright 2014 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.
 
 package org.chromium.chrome.browser.init;
 
 import android.app.Activity;
 import android.content.Context;
 import android.os.AsyncTask;
 import android.os.Build;
@@ skipping 95 matching lines @@
     }
 
     @RemovableInRelease
     private void initLeakCanary() {
         // Watch that Activity objects are not retained after their onDestroy() has been called.
         // This is a no-op in release builds.
         LeakCanary.install(mApplication);
     }
 
     /**
+     * @return whether native initialization is complete.
+     */
+    public boolean hasNativeInitializationCompleted() {

[Yusuf, 2017/07/06 06:34:42]

hasAppLevelNativeInitializationCompleted? since Activity level native init might
still be going on/

[Benoit L, 2017/07/07 11:30:56]

The whole call is ChromeBrowserInitializer.hasNativeInitializationCompleted(),
isn't it explicit enough?

+        return mNativeInitializationComplete;
+    }
+
+    /**
      * Initializes the Chrome browser process synchronously.
      *
      * @throws ProcessInitException if there is a problem with the native library.
      */
     public void handleSynchronousStartup() throws ProcessInitException {
         handleSynchronousStartupInternal(false);
     }
 
     /**
      * Initializes the Chrome browser process synchronously with GPU process warmup.
@@ skipping 319 matching lines @@
     }
 
     /**
      * For unit testing of clients.
      * @param initializer The (dummy or mocked) initializer to use.
      */
     public static void setForTesting(ChromeBrowserInitializer initializer) {
         sChromeBrowserInitializer = initializer;
     }
 }