Delegating the "are images allowed" decision to renderer.

chrome/common/content_settings.h

Index: chrome/common/content_settings.h
diff --git a/chrome/common/content_settings.h b/chrome/common/content_settings.h
index 4731263f7d15d5a891598d56bac153374421f53d..68c456a5c70d542462cbf3c9d848837c11ced621 100644
--- a/chrome/common/content_settings.h
+++ b/chrome/common/content_settings.h
@@ -6,6 +6,11 @@
 #define CHROME_COMMON_CONTENT_SETTINGS_H_
 #pragma once
 
+#include <string>
+#include <vector>
+
+#include "base/tuple.h"
+#include "chrome/common/content_settings_pattern.h"
 #include "chrome/common/content_settings_types.h"
 
 // Different settings that can be assigned for a particular content type.  We
@@ -38,4 +43,11 @@ struct ContentSettings {
   ContentSetting settings[CONTENT_SETTINGS_NUM_TYPES];
 };
 
+// For transmitting content settings over IPC.
+typedef Tuple3<ContentSettingsPattern,
+               ContentSettingsPattern,
+               ContentSetting> ContentSettingPatternTuple;
+
+typedef std::vector<ContentSettingPatternTuple> ContentSettingRules;
+
 #endif  // CHROME_COMMON_CONTENT_SETTINGS_H_