easy-unlock: Fix AttemptAuth email CHECK crash

- Return canonicalized email from GetUserEmail because sign-in
  manager gives back the Gaia email which is not necessarily the
  same as the one used on the login screen;
- Sign-in manager gives empty user email when underlying refresh token
  is revoked. Bail out in this case.

BUG=489890

Review URL: https://codereview.chromium.org/1149873003

Cr-Commit-Position: refs/heads/master@{#330890}

chrome/browser/signin/easy_unlock_service.cc

@@ -493,13 +493,24 @@ void EasyUnlockService::AttemptAuth(const std::string& user_id) {
 
 void EasyUnlockService::AttemptAuth(const std::string& user_id,
                                     const AttemptAuthCallback& callback) {
+  const EasyUnlockAuthAttempt::Type auth_attempt_type =
+      GetType() == TYPE_REGULAR ? EasyUnlockAuthAttempt::TYPE_UNLOCK
+                                : EasyUnlockAuthAttempt::TYPE_SIGNIN;
+  const std::string user_email = GetUserEmail();
+  if (user_email.empty()) {
+    LOG(ERROR) << "Empty user email. Refresh token might go bad.";
+    if (!callback.is_null()) {
+      const bool kFailure = false;
+      callback.Run(auth_attempt_type, kFailure, user_id, std::string(),
+                   std::string());
+    }
+    return;
+  }
+
   CHECK_EQ(GetUserEmail(), user_id);
 
-  auth_attempt_.reset(new EasyUnlockAuthAttempt(
-      app_manager_.get(), user_id,
-      GetType() == TYPE_REGULAR ? EasyUnlockAuthAttempt::TYPE_UNLOCK
-                                : EasyUnlockAuthAttempt::TYPE_SIGNIN,
-      callback));
+  auth_attempt_.reset(new EasyUnlockAuthAttempt(app_manager_.get(), user_id,
+                                                auth_attempt_type, callback));
   if (!auth_attempt_->Start())
     auth_attempt_.reset();
 }

chrome/browser/signin/easy_unlock_service_regular.cc

@@ -31,6 +31,7 @@
 #include "content/public/browser/browser_thread.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/common/constants.h"
+#include "google_apis/gaia/gaia_auth_util.h"
 
 #if defined(OS_CHROMEOS)
 #include "apps/app_lifetime_monitor_factory.h"
@@ -98,7 +99,8 @@ std::string EasyUnlockServiceRegular::GetUserEmail() const {
   // |profile| has to be a signed-in profile with SigninManager already
   // created. Otherwise, just crash to collect stack.
   DCHECK(signin_manager);
-  return signin_manager->GetAuthenticatedUsername();
+  const std::string user_email = signin_manager->GetAuthenticatedUsername();
+  return user_email.empty() ? user_email : gaia::CanonicalizeEmail(user_email);
 }
 
 void EasyUnlockServiceRegular::LaunchSetup() {