Differentiate new permissions from old in extension permission update bubble

extensions/common/permissions/permissions_data.cc

 // Copyright (c) 2013 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 "extensions/common/permissions/permissions_data.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/command_line.h"
@@ skipping 279 matching lines @@
   return active_permissions_unsafe_->HasEffectiveAccessToAllHosts();
 }
 
 PermissionMessages PermissionsData::GetPermissionMessages() const {
   base::AutoLock auto_lock(runtime_lock_);
   return PermissionMessageProvider::Get()->GetPermissionMessages(
       PermissionMessageProvider::Get()->GetAllPermissionIDs(
           *active_permissions_unsafe_, manifest_type_));
 }
 
+PermissionMessages PermissionsData::GetNewPermissionMessages(
+    const PermissionSet& granted_permissions) const {
+  base::AutoLock auto_lock(runtime_lock_);
+
+  std::unique_ptr<const PermissionSet> new_permissions =
+      PermissionSet::CreateDifference(*active_permissions_unsafe_,
+                                      granted_permissions);
+
+  return PermissionMessageProvider::Get()->GetPermissionMessages(
+      PermissionMessageProvider::Get()->GetAllPermissionIDs(*new_permissions,
+                                                            manifest_type_));
+}
+
 bool PermissionsData::HasWithheldImpliedAllHosts() const {
   base::AutoLock auto_lock(runtime_lock_);
   // Since we currently only withhold all_hosts, it's sufficient to check
   // that either set is not empty.
   return !withheld_permissions_unsafe_->explicit_hosts().is_empty() ||
          !withheld_permissions_unsafe_->scriptable_hosts().is_empty();
 }
 
 bool PermissionsData::CanAccessPage(const Extension* extension,
                                     const GURL& document_url,
@@ skipping 135 matching lines @@
           manifest_errors::kCannotAccessPageWithUrl, document_url.spec());
     } else {
       *error = manifest_errors::kCannotAccessPage;
     }
   }
 
   return ACCESS_DENIED;
 }
 
 }  // namespace extensions