[Autofill] Add support for signin promo on Android

chrome/chrome_browser.gypi

Index: chrome/chrome_browser.gypi
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index 3b94763ac6081fcef9da4b61919fcec338d1fffb..6c5133ba31169d73a1d84fb9868e21b05cf41653 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -976,6 +976,8 @@
       'browser/android/signin/signin_investigator_android.h',
       'browser/android/signin/signin_manager_android.cc',
       'browser/android/signin/signin_manager_android.h',
+      'browser/android/signin/signin_promo_util_android.cc',
+      'browser/android/signin/signin_promo_util_android.h',
       'browser/android/tab_android.cc',
       'browser/android/tab_android.h',
       'browser/android/tab_state.cc',
@@ -2072,6 +2074,7 @@
       'android/java/src/org/chromium/chrome/browser/signin/OAuth2TokenService.java',
       'android/java/src/org/chromium/chrome/browser/signin/SigninInvestigator.java',
       'android/java/src/org/chromium/chrome/browser/signin/SigninManager.java',
+      'android/java/src/org/chromium/chrome/browser/signin/SigninPromoUtil.java',
       'android/java/src/org/chromium/chrome/browser/snackbar/smartlockautosignin/AutoSigninSnackbarController.java',
       'android/java/src/org/chromium/chrome/browser/spellchecker/SpellCheckerSessionBridge.java',
       'android/java/src/org/chromium/chrome/browser/superviseduser/SupervisedUserContentProvider.java',
@@ -2899,6 +2902,8 @@
       'browser/signin/signin_error_controller_factory.h',
       'browser/signin/signin_manager_factory.cc',
       'browser/signin/signin_manager_factory.h',
+      'browser/signin/signin_promo_util.cc',
+      'browser/signin/signin_promo_util.h',
       'browser/signin/signin_status_metrics_provider_chromeos.cc',
       'browser/signin/signin_status_metrics_provider_chromeos.h',
       'browser/signin/signin_tracker_factory.cc',