Delegating the "are images allowed" decision to renderer.

chrome/browser/content_settings/content_settings_provider.h

Index: chrome/browser/content_settings/content_settings_provider.h
diff --git a/chrome/browser/content_settings/content_settings_provider.h b/chrome/browser/content_settings/content_settings_provider.h
index 466c9cddfe0d058df1c9c102d30793612e1667db..269cc701bbfde6a4bd19ff267363cf201e1c8ba8 100644
--- a/chrome/browser/content_settings/content_settings_provider.h
+++ b/chrome/browser/content_settings/content_settings_provider.h
@@ -50,6 +50,9 @@ class DefaultProviderInterface {
 class ProviderInterface {
  public:
   struct Rule {
+    typedef bool (*SortFunction)(
+        const ProviderInterface::Rule&,
+        const ProviderInterface::Rule&);
     Rule();
     Rule(const ContentSettingsPattern& primary_pattern,
          const ContentSettingsPattern& secondary_pattern,
@@ -58,6 +61,14 @@ class ProviderInterface {
     ContentSettingsPattern primary_pattern;
     ContentSettingsPattern secondary_pattern;
     ContentSetting content_setting;
+
+    static bool LexicographicalSort(
+        const ProviderInterface::Rule& a,
+        const ProviderInterface::Rule& b);
+
+    static bool PatternPrecedenceSort(
+        const ProviderInterface::Rule& a,
+        const ProviderInterface::Rule& b);
   };
 
   typedef std::vector<Rule> Rules;