Extensions: Make it possible for permission parsing code to return a detailed error message.

chrome/common/extensions/permissions/bluetooth_permission.cc

 // Copyright 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 "chrome/common/extensions/permissions/bluetooth_permission.h"
 
 #include <string>
 
 #include "base/logging.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/common/extensions/permissions/bluetooth_permission_data.h"
 #include "extensions/common/permissions/permissions_info.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 
 namespace extensions {
 
 BluetoothPermission::BluetoothPermission(const APIPermissionInfo* info)
   : SetDisjunctionPermission<BluetoothPermissionData,
                              BluetoothPermission>(info) {
 }
 
 BluetoothPermission::~BluetoothPermission() {
 }
 
-bool BluetoothPermission::FromValue(const base::Value* value) {
+bool BluetoothPermission::FromValue(const base::Value* value,
+                                    std::string* error) {
   // Value may be omitted to gain access to non-profile functions.
   if (!value)
     return true;
 
   // Value may be an empty list for the same reason.
   const base::ListValue* list = NULL;
   if (value->GetAsList(&list) && list->GetSize() == 0)
     return true;
 
   if (!SetDisjunctionPermission<BluetoothPermissionData,
-                                BluetoothPermission>::FromValue(value)) {
+                                BluetoothPermission>::FromValue(value, error)) {
     return false;
   }
 
   return true;
 }
 
 PermissionMessages BluetoothPermission::GetMessages() const {
   DCHECK(HasMessages());
   PermissionMessages result;
 
   result.push_back(PermissionMessage(
         PermissionMessage::kBluetooth,
         l10n_util::GetStringUTF16(
             IDS_EXTENSION_PROMPT_WARNING_BLUETOOTH)));
 
   if (!data_set_.empty()) {
     result.push_back(PermissionMessage(
           PermissionMessage::kBluetoothDevices,
           l10n_util::GetStringUTF16(
               IDS_EXTENSION_PROMPT_WARNING_BLUETOOTH_DEVICES)));
   }
 
   return result;
 }
 
 }  // namespace extensions