Convert AutoBlocker static class to KeyedService.

chrome/browser/permissions/permission_blacklist_client.h

 // Copyright 2017 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_PERMISSIONS_PERMISSION_BLACKLIST_CLIENT_H_
 #define CHROME_BROWSER_PERMISSIONS_PERMISSION_BLACKLIST_CLIENT_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "chrome/browser/permissions/permission_util.h"
@@ skipping 13 matching lines @@
 
 // The client used when checking whether a permission has been blacklisted by
 // Safe Browsing. The check is done asynchronously as no state can be stored in
 // PermissionContextBase (since additional permission requests may be made).
 // This class must be created and destroyed on the UI thread.
 class PermissionBlacklistClient
     : public safe_browsing::SafeBrowsingDatabaseManager::Client,
       public base::RefCountedThreadSafe<PermissionBlacklistClient>,
       public content::WebContentsObserver {
  public:
+  // |callback| will not be called if |web_contents| is destroyed. Thus if the
+  // callback is run, the profile associated with |web_contents| is guaranteed
+  // to be alive.
   static void CheckSafeBrowsingBlacklist(
       scoped_refptr<safe_browsing::SafeBrowsingDatabaseManager> db_manager,
       content::PermissionType permission_type,
       const GURL& request_origin,
       content::WebContents* web_contents,
       int timeout,
       base::Callback<void(bool)> callback);
 
  private:
   friend class base::RefCountedThreadSafe<PermissionBlacklistClient>;
@@ skipping 34 matching lines @@
   int timeout_;
 
   // True if |callback_| should be invoked, if web_contents() is destroyed, this
   // is set to false.
   bool is_active_;
 
   DISALLOW_COPY_AND_ASSIGN(PermissionBlacklistClient);
 };
 
 #endif  // CHROME_BROWSER_PERMISSIONS_PERMISSION_BLACKLIST_CLIENT_H_