Remove the allow-displaying-mixed-content setting from Blink.

chrome/browser/ui/prefs/prefs_tab_helper.cc

Index: chrome/browser/ui/prefs/prefs_tab_helper.cc
diff --git a/chrome/browser/ui/prefs/prefs_tab_helper.cc b/chrome/browser/ui/prefs/prefs_tab_helper.cc
index d22384c4d1877bb40b8a4ac28a92f01ffc8aff34..e20387908a0447d1bc1aabbb79a2c70375423c1d 100644
--- a/chrome/browser/ui/prefs/prefs_tab_helper.cc
+++ b/chrome/browser/ui/prefs/prefs_tab_helper.cc
@@ -73,7 +73,6 @@ const char* kPrefsToObserve[] = {
   prefs::kDefaultCharset,
   prefs::kDisable3DAPIs,
   prefs::kEnableHyperlinkAuditing,
-  prefs::kWebKitAllowDisplayingInsecureContent,
   prefs::kWebKitAllowRunningInsecureContent,
   prefs::kWebKitDefaultFixedFontSize,
   prefs::kWebKitDefaultFontSize,
@@ -523,8 +522,6 @@ void PrefsTabHelper::RegisterProfilePrefs(
                                 pref_defaults.tabs_to_links);
   registry->RegisterBooleanPref(prefs::kWebKitAllowRunningInsecureContent,
                                 false);
-  registry->RegisterBooleanPref(prefs::kWebKitAllowDisplayingInsecureContent,
-                                true);
   registry->RegisterBooleanPref(prefs::kEnableReferrers, true);
 #if defined(OS_ANDROID)
   registry->RegisterDoublePref(prefs::kWebKitFontScaleFactor, 1.0);