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

chrome/browser/chrome_content_browser_client.cc

 // Copyright (c) 2012 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/browser/chrome_content_browser_client.h"
 
 #include <map>
 #include <set>
 #include <utility>
 #include <vector>
@@ skipping 2373 matching lines @@
   }
 
   if (!prefs->GetBoolean(prefs::kWebKitPluginsEnabled))
     web_prefs->plugins_enabled = false;
   web_prefs->loads_images_automatically =
       prefs->GetBoolean(prefs::kWebKitLoadsImagesAutomatically);
 
   if (prefs->GetBoolean(prefs::kDisable3DAPIs))
     web_prefs->experimental_webgl_enabled = false;
 
-  web_prefs->allow_displaying_insecure_content =
-      prefs->GetBoolean(prefs::kWebKitAllowDisplayingInsecureContent);
   web_prefs->allow_running_insecure_content =
       prefs->GetBoolean(prefs::kWebKitAllowRunningInsecureContent);
 #if defined(OS_ANDROID)
   web_prefs->font_scale_factor =
       static_cast<float>(prefs->GetDouble(prefs::kWebKitFontScaleFactor));
   web_prefs->device_scale_adjustment = GetDeviceScaleAdjustment();
   web_prefs->force_enable_zoom =
       prefs->GetBoolean(prefs::kWebKitForceEnableZoom);
 #endif
 
@@ skipping 771 matching lines @@
   if (channel <= kMaxDisableEncryptionChannel) {
     static const char* const kWebRtcDevSwitchNames[] = {
       switches::kDisableWebRtcEncryption,
     };
     to_command_line->CopySwitchesFrom(from_command_line,
                                       kWebRtcDevSwitchNames,
                                       arraysize(kWebRtcDevSwitchNames));
   }
 }
 #endif  // defined(ENABLE_WEBRTC)