[unified-consent] Update 'Learn More' link for Sync and Google services

Changes of this CL:
 - The learn-more link for Sync and Google services is only shown
 when unified consent is enabled.
 - The learn-more link is updated and now redirects to
 https://support.google.com/chrome?p=syncgoogleservices.

Bug: 875869, 875748
Change-Id: Ieeffa33da578d5bb22e547246cd12d285c26c390
Reviewed-on: https://chromium-review.googlesource.com/1181428Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Commit-Queue: Thomas Tangl <tangltom@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584696}

chrome/browser/resources/settings/people_page/people_page.html

@@ -353,7 +353,7 @@
         <settings-subpage
             associated-control="[[$$('#sync-status')]]"
             page-title="$i18n{syncPageTitle}"
-            learn-more-url="$i18n{privacyLearnMoreURL}"
+            learn-more-url="$i18n{syncAndGoogleServicesLearnMoreURL}"
             no-search$="[[!isAdvancedSyncSettingsVisible_(syncStatus,
                 unifiedConsentEnabled_)]]">
           <settings-sync-page

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

@@ -2013,7 +2013,10 @@ void AddPrivacyStrings(content::WebUIDataSource* html_source,
                             arraysize(conditional_localized_strings));
   }
 
-  html_source->AddString("privacyLearnMoreURL", chrome::kPrivacyLearnMoreURL);
+  html_source->AddString("syncAndGoogleServicesLearnMoreURL",
+                         IsUnifiedConsentEnabled(profile)
+                             ? chrome::kSyncAndGoogleServicesLearnMoreURL
+                             : "");
   html_source->AddString(
       "improveBrowsingExperience",
       l10n_util::GetStringFUTF16(

chrome/common/url_constants.cc

@@ -199,6 +199,9 @@ const char kSettingsSearchHelpURL[] =
 const char kSmartLockHelpPage[] =
     "https://support.google.com/accounts/answer/6197437";
 
+const char kSyncAndGoogleServicesLearnMoreURL[] =
+    "https://support.google.com/chrome?p=syncgoogleservices";
+
 const char kSyncEncryptionHelpURL[] =
 #if defined(OS_CHROMEOS)
     "https://support.google.com/chromebook/?p=settings_encryption";

chrome/common/url_constants.h

@@ -167,6 +167,9 @@ extern const char kSettingsSearchHelpURL[];
 
 extern const char kSmartLockHelpPage[];
 
+// The URL for the Learn More page about Sync and Google services.
+extern const char kSyncAndGoogleServicesLearnMoreURL[];
+
 // The URL for the "Learn more" page on sync encryption.
 extern const char kSyncEncryptionHelpURL[];