Add a "guard" content settings type for chooser permissions.

chrome/browser/permissions/chooser_context_base.cc

 // Copyright 2015 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/browser/permissions/chooser_context_base.h"
 
 #include <string>
 
 #include "base/values.h"
 #include "chrome/browser/content_settings/host_content_settings_map_factory.h"
 #include "components/content_settings/core/browser/host_content_settings_map.h"
 
 using ObjectList = ScopedVector<base::DictionaryValue>;
 
 const char kObjectListKey[] = "chosen-objects";
 
 ChooserContextBase::ChooserContextBase(
     Profile* profile,
+    const ContentSettingsType guard_content_settings_type,
     const ContentSettingsType data_content_settings_type)
     : host_content_settings_map_(
           HostContentSettingsMapFactory::GetForProfile(profile)),
+      guard_content_settings_type_(guard_content_settings_type),
       data_content_settings_type_(data_content_settings_type) {
   DCHECK(host_content_settings_map_);
 }
 
 ChooserContextBase::~ChooserContextBase() {}
 
+bool ChooserContextBase::CanRequestObjectPermission(
+    const GURL& requesting_origin,
+    const GURL& embedding_origin) {
+  ContentSetting content_setting =
+      host_content_settings_map_->GetContentSetting(
+          requesting_origin, embedding_origin, guard_content_settings_type_,
+          std::string());
+  return content_setting == CONTENT_SETTING_ALLOW;
+}
+
 ObjectList ChooserContextBase::GetGrantedObjects(const GURL& requesting_origin,
                                                  const GURL& embedding_origin) {
+  if (!CanRequestObjectPermission(requesting_origin, embedding_origin))
+    return ObjectList();
+
   scoped_ptr<base::DictionaryValue> setting =
       GetWebsiteSetting(requesting_origin, embedding_origin);
   scoped_ptr<base::Value> objects;
   if (!setting->Remove(kObjectListKey, &objects))
     return ObjectList();
 
   scoped_ptr<base::ListValue> object_list =
       base::ListValue::From(objects.Pass());
   if (!object_list)
     return ObjectList();
@@ skipping 10 matching lines @@
     if (object_dict && IsValidObject(*object_dict))
       results.push_back(object_dict.Pass());
   }
   return results.Pass();
 }
 
 void ChooserContextBase::GrantObjectPermission(
     const GURL& requesting_origin,
     const GURL& embedding_origin,
     scoped_ptr<base::DictionaryValue> object) {
-  DCHECK(object && IsValidObject(*object));
+  DCHECK(object);
+  DCHECK(IsValidObject(*object));
+  DCHECK(CanRequestObjectPermission(requesting_origin, embedding_origin));
   scoped_ptr<base::DictionaryValue> setting =
       GetWebsiteSetting(requesting_origin, embedding_origin);
   base::ListValue* object_list;
   if (!setting->GetList(kObjectListKey, &object_list)) {
     object_list = new base::ListValue();
     setting->Set(kObjectListKey, object_list);
   }
   object_list->AppendIfNotPresent(object.release());
   SetWebsiteSetting(requesting_origin, embedding_origin, setting.Pass());
 }
@@ skipping 32 matching lines @@
       ContentSettingsPattern::FromURLNoWildcard(requesting_origin));
   ContentSettingsPattern secondary_pattern(
       ContentSettingsPattern::FromURLNoWildcard(embedding_origin));
   if (!primary_pattern.IsValid() || !secondary_pattern.IsValid())
     return;
 
   host_content_settings_map_->SetWebsiteSetting(
       primary_pattern, secondary_pattern, data_content_settings_type_,
       std::string(), value.release());
 }