Prevent unnecessary prompts when unpacked extensions use chrome.permissions.request.

chrome/common/extensions/extension.h

 // Copyright (c) 2012 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_COMMON_EXTENSIONS_EXTENSION_H_
 #define CHROME_COMMON_EXTENSIONS_EXTENSION_H_
 #pragma once
 
 #include <map>
 #include <set>
@@ skipping 378 matching lines @@
                         string16* error,
                         ExtensionAPIPermissionSet* api_permissions,
                         URLPatternSet* host_permissions);
 
   bool HasAPIPermission(ExtensionAPIPermission::ID permission) const;
   bool HasAPIPermission(const std::string& function_name) const;
 
   const URLPatternSet& GetEffectiveHostPermissions() const;
 
   // Returns true if the extension can silently increase its permission level.
-  // Extensions that can silently increase permissions are installed through
-  // mechanisms that are implicitly trusted.
+  // Users must approve permissions for unpacked and packed extensions in the
+  // following situations:
+  //  - when installing or upgrading packed extensions
+  //  - when installing unpacked extensions that have NPAPI plugins
+  //  - when either type of extension requests optional permissions
   bool CanSilentlyIncreasePermissions() const;
 
-
   // Whether the extension has access to the given URL.
   bool HasHostPermission(const GURL& url) const;
 
   // Whether the extension has effective access to all hosts. This is true if
   // there is a content script that matches all hosts, if there is a host
   // permission grants access to all hosts (like <all_urls>) or an api
   // permission that effectively grants access to all hosts (e.g. proxy,
   // network, etc.)
   bool HasEffectiveAccessToAllHosts() const;
 
@@ skipping 542 matching lines @@
   // only contain the removed permissions.
   const ExtensionPermissionSet* permissions;
 
   UpdatedExtensionPermissionsInfo(
       const Extension* extension,
       const ExtensionPermissionSet* permissions,
       Reason reason);
 };
 
 #endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_H_