Add a global on/off switch for content settings and expose a toggle on the Website Settings options…

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index 33ead5e7d3095050b3367111654526a9c820e062..2c8c07d9df79e860f9a10a0377a06007261c36aa 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -990,6 +990,10 @@ const char kUseCustomChromeFrame[] = "browser.custom_chrome_frame";
 // Dictionary of content settings applied to all hosts by default.
 const char kDefaultContentSettings[] = "profile.default_content_settings";
 
+// Dictionary of content settings that can globally disallow all hosts by
+// default.
+const char kOverrideContentSettings[] = "profile.override_content_settings";
+
 // Boolean indicating whether the clear on exit pref was migrated to content
 // settings yet.
 const char kContentSettingsClearOnExitMigrated[] =