Remove the (broken and unneeded) 'force_update' option from ServiceWatcher::DiscoverNewDevices.

chrome/browser/devtools/device/cast_device_provider.cc

 // Copyright 2015 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/devtools/device/cast_device_provider.h"
 
 #include <map>
 #include <set>
 #include <string>
+#include <utility>
 #include <vector>
 
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "chrome/browser/local_discovery/service_discovery_shared_client.h"
 #include "net/base/host_port_pair.h"
 #include "net/base/ip_address.h"
 
@@ skipping 77 matching lines @@
   void StartDiscovery() {
     // This must be called on the UI thread; ServiceDiscoverySharedClient and
     // ServiceDiscoveryDeviceLister are thread protected.
     DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
     if (device_lister_)
       return;
     service_discovery_client_ = ServiceDiscoverySharedClient::GetInstance();
     device_lister_.reset(new ServiceDiscoveryDeviceLister(
         this, service_discovery_client_.get(), kCastServiceType));
     device_lister_->Start();
-    device_lister_->DiscoverNewDevices(true);
+    device_lister_->DiscoverNewDevices();
   }
 
   // ServiceDiscoveryDeviceLister::Delegate implementation:
   void OnDeviceChanged(bool added,
                        const ServiceDescription& service_description) override {
     runner_->PostTask(FROM_HERE,
                       base::BindOnce(&CastDeviceProvider::OnDeviceChanged,
                                      provider_, added, service_description));
   }
 
@@ skipping 79 matching lines @@
   const std::string& hostname = it->second;
   device_info_map_.erase(hostname);
   service_hostname_map_.erase(it);
 }
 
 void CastDeviceProvider::OnDeviceCacheFlushed() {
   VLOG(1) << "Device cache flushed";
   service_hostname_map_.clear();
   device_info_map_.clear();
 }