Ensure settings returned from Content Settings providers are valid

components/content_settings/core/browser/content_settings_info.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 "components/content_settings/core/browser/content_settings_info.h"
 
 #include "base/stl_util.h"
+#include "components/content_settings/core/browser/website_settings_info.h"
 
 namespace content_settings {
 
 ContentSettingsInfo::ContentSettingsInfo(
     const WebsiteSettingsInfo* website_settings_info,
     const std::vector<std::string>& whitelisted_schemes,
     const std::set<ContentSetting>& valid_settings,
     IncognitoBehavior incognito_behavior)
     : website_settings_info_(website_settings_info),
       whitelisted_schemes_(whitelisted_schemes),
       valid_settings_(valid_settings),
       incognito_behavior_(incognito_behavior) {}
 
 ContentSettingsInfo::~ContentSettingsInfo() {}
 
 bool ContentSettingsInfo::IsSettingValid(ContentSetting setting) const {
   return base::ContainsKey(valid_settings_, setting);
 }
 
+// TODO(raymes): Find a better way to deal with the special-casing in
+// IsDefaultSettingValid.
+bool ContentSettingsInfo::IsDefaultSettingValid(ContentSetting setting) const {
+  ContentSettingsType type = website_settings_info_->type();
+#if defined(OS_ANDROID) || defined(OS_CHROMEOS)
+  // Don't support ALLOW for protected media default setting until migration.
+  if (type == CONTENT_SETTINGS_TYPE_PROTECTED_MEDIA_IDENTIFIER &&
+      setting == CONTENT_SETTING_ALLOW) {
+    return false;
+  }
+#endif
+
+  // Don't support ALLOW for the default media settings.
+  if ((type == CONTENT_SETTINGS_TYPE_MEDIASTREAM_CAMERA ||
+       type == CONTENT_SETTINGS_TYPE_MEDIASTREAM_MIC) &&
+      setting == CONTENT_SETTING_ALLOW) {
+    return false;
+  }
+
+  return base::ContainsKey(valid_settings_, setting);
+}
+
 }  // namespace content_settings