Implement debugging local unlock keys in chrome://proximity-auth.

chrome/browser/signin/easy_unlock_service.cc

Index: chrome/browser/signin/easy_unlock_service.cc
diff --git a/chrome/browser/signin/easy_unlock_service.cc b/chrome/browser/signin/easy_unlock_service.cc
index 4ccbcda307e4020cac3f421746b0838d3a5579ab..6e6707ba42fbf9668cf63e3cc90e16445f03e3cb 100644
--- a/chrome/browser/signin/easy_unlock_service.cc
+++ b/chrome/browser/signin/easy_unlock_service.cc
@@ -687,6 +687,11 @@ cryptauth::DeviceClassifier EasyUnlockService::GetDeviceClassifier() {
   return device_classifier;
 }
 
+std::string EasyUnlockService::GetAccountId() {
+  return SigninManagerFactory::GetForProfile(profile())
+      ->GetAuthenticatedAccountId();
+}
+
 gcm::GCMDriver* EasyUnlockService::GetGCMDriver() {
   gcm::GCMProfileService* gcm_profile_service =
       gcm::GCMProfileServiceFactory::GetForProfile(profile_);