Rename the "Advanced security" section to just "Advanced"

Per UI feedback. We can simply reuse the existing "Advanced" string from
the main settings page, as its string resource description fits the new
use as well.

The previous string is not used anywhere else, and can be removed.

Bug: 1069601
Change-Id: Iba34a77e33b3ad4d7dc4f8abd55d35a684bbf2fd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2144043Reviewed-by: Esmael Elmoslimany <aee@chromium.org>
Commit-Queue: Martin Šrámek <msramek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#758045}

chrome/app/settings_strings.grdp

@@ -1211,10 +1211,6 @@
   <message name="IDS_SETTINGS_SECURITY_DESCRIPTION" desc="Description of the controls available on the security settings page">
     Safe Browsing (protection from dangerous sites) and other security settings
   </message>
-  <message name="IDS_SETTINGS_SECURITY_ADVANCED_SECTION_LABEL" desc="Name of the section in the
-    security settings page which groups advanced security settings">
-    Advanced security
-  </message>
   <message name="IDS_SETTINGS_ADVANCED_PROTECTION_PROGRAM" desc="Name of the link which takes users
     to the Google Advanced Protection Program external webpage">
     Google Advanced Protection Program

chrome/browser/resources/settings/privacy_page/security_page.html

@@ -176,7 +176,7 @@
       </cr-radio-group>
     </div>
     <div class="settings-box first line-only">
-      <h2>$i18n{securityPageAdvancedSectionLabel}</h2>
+      <h2>$i18n{advancedPageTitle}</h2>
     </div>
     <template is="dom-if" if="[[showSecureDnsSetting_]]">
       <settings-secure-dns prefs="{{prefs}}"></settings-secure-dns>

chrome/browser/ui/webui/settings/settings_localized_strings_provider.cc

@@ -1110,8 +1110,6 @@ void AddPrivacyStrings(content::WebUIDataSource* html_source,
       {"permissionsPageDescription", IDS_SETTINGS_PERMISSIONS_DESCRIPTION},
       {"securityPageTitle", IDS_SETTINGS_SECURITY},
       {"securityPageDescription", IDS_SETTINGS_SECURITY_DESCRIPTION},
-      {"securityPageAdvancedSectionLabel",
-       IDS_SETTINGS_SECURITY_ADVANCED_SECTION_LABEL},
       {"advancedProtectionProgramTitle",
        IDS_SETTINGS_ADVANCED_PROTECTION_PROGRAM},
       {"advancedProtectionProgramDesc",