[MD settings] clear incognito only checkbox

chrome/browser/resources/settings/site_settings/add_site_dialog.js

Index: chrome/browser/resources/settings/site_settings/add_site_dialog.js
diff --git a/chrome/browser/resources/settings/site_settings/add_site_dialog.js b/chrome/browser/resources/settings/site_settings/add_site_dialog.js
index 41eecca19c87a1f0f710a7097fbe8d47d099c78f..ae6963424d99713189dcccf1ea0935b486435a95 100644
--- a/chrome/browser/resources/settings/site_settings/add_site_dialog.js
+++ b/chrome/browser/resources/settings/site_settings/add_site_dialog.js
@@ -47,8 +47,9 @@ Polymer({
    *     Block list.
    */
   open: function(type) {
-    this.addWebUIListener('onIncognitoStatusChanged', function(isActive) {
-      this.showIncognitoSessionOnly_ = isActive &&
+    this.addWebUIListener('onIncognitoStatusChanged', function(hasIncognito) {
+      this.$.incognito.checked = false;
+      this.showIncognitoSessionOnly_ = hasIncognito &&
           this.contentSetting != settings.PermissionValues.SESSION_ONLY;
     }.bind(this));
     this.browserProxy.updateIncognitoStatus();