Revert of Hook up ProximityAuthSystem in EasyUnlockService.

chrome/browser/signin/easy_unlock_auth_attempt.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/signin/easy_unlock_auth_attempt.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "chrome/browser/signin/easy_unlock_app_manager.h"
@@ skipping 100 matching lines @@
       proximity_auth::ScreenlockBridge::Get()->lock_handler()->GetAuthType(
           user_id_);
 
   if (auth_type != proximity_auth::ScreenlockBridge::LockHandler::USER_CLICK) {
     Cancel(user_id_);
     return false;
   }
 
   state_ = STATE_RUNNING;
 
-  if (!app_manager_->SendAuthAttemptEvent()) {
+  // We need this workaround for ProximityAuthBleSystem, which is already
+  // notified in EasyUnlockService. No notification is sent when only the
+  // |kEnableBluetoothLowEnergyDiscovery| flag is set, and
+  // |app_manager_->SendAuthAttemptEvent()| returns false. As a result, the auth
+  // attempt will always fail.
+  // TODO(sacomoto): Remove this when it's not needed anymore.
+  if (!app_manager_->SendAuthAttemptEvent() &&
+      !base::CommandLine::ForCurrentProcess()->HasSwitch(
+          proximity_auth::switches::kEnableBluetoothLowEnergyDiscovery)) {
     Cancel(user_id_);
     return false;
   }
 
   return true;
 }
 
 void EasyUnlockAuthAttempt::FinalizeUnlock(const std::string& user_id,
                                            bool success) {
   if (state_ != STATE_RUNNING || user_id != user_id_)
@@ skipping 44 matching lines @@
   state_ = STATE_DONE;
 }
 
 void EasyUnlockAuthAttempt::Cancel(const std::string& user_id) {
   state_ = STATE_DONE;
 
   const bool kFailure = false;
   finalized_callback_.Run(type_, kFailure, user_id, std::string(),
                           std::string());
 }