Delegating the "are images allowed" decision to renderer.

chrome/common/content_settings.cc

 // Copyright (c) 2010 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/content_settings.h"
 
 ContentSetting IntToContentSetting(int content_setting) {
   return ((content_setting < 0) ||
           (content_setting >= CONTENT_SETTING_NUM_SETTINGS)) ?
       CONTENT_SETTING_DEFAULT : static_cast<ContentSetting>(content_setting);
 }
+
+ContentSettingPatternSource::ContentSettingPatternSource(
+    const ContentSettingsPattern& primary_pattern,
+    const ContentSettingsPattern& secondary_pattern,
+    ContentSetting setting,
+    const std::string& source,
+    bool incognito)
+    : primary_pattern(primary_pattern),
+      secondary_pattern(secondary_pattern),
+      setting(setting),
+      source(source),
+      incognito(incognito) {}
+
+ContentSettingPatternSource::ContentSettingPatternSource() {}