Remove threading from WifiDataProviderCommon.

content/browser/geolocation/wifi_data_provider_common.cc

 // Copyright (c) 2012 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 "content/browser/geolocation/wifi_data_provider_common.h"
 
 #include "base/bind.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 
 namespace content {
 
 string16 MacAddressAsString16(const uint8 mac_as_int[6]) {
   // mac_as_int is big-endian. Write in byte chunks.
   // Format is XX-XX-XX-XX-XX-XX.
   static const char* const kMacFormatString =
       "%02x-%02x-%02x-%02x-%02x-%02x";
   return ASCIIToUTF16(base::StringPrintf(kMacFormatString,
                                         mac_as_int[0],
                                         mac_as_int[1],
                                         mac_as_int[2],
                                         mac_as_int[3],
                                         mac_as_int[4],
                                         mac_as_int[5]));
 }
 
 WifiDataProviderCommon::WifiDataProviderCommon()
-    : Thread("Geolocation_wifi_provider"),
-      is_first_scan_complete_(false),
+    : is_first_scan_complete_(false),
       weak_factory_(this) {
 }
 
 WifiDataProviderCommon::~WifiDataProviderCommon() {
-  // Thread must be stopped before entering destructor chain to avoid race
-  // conditions; see comment in DeviceDataProvider::Unregister.
-  DCHECK(!IsRunning());  // Must call StopDataProvider before destroying me.
 }
 
-bool WifiDataProviderCommon::StartDataProvider() {
-  DCHECK(CalledOnClientThread());
-  DCHECK(!IsRunning());  // StartDataProvider must only be called once.
-  return Start();
-}
-
-void WifiDataProviderCommon::StopDataProvider() {
-  DCHECK(CalledOnClientThread());
-  Stop();
-}
-
-bool WifiDataProviderCommon::GetData(WifiData* data) {
-  DCHECK(CalledOnClientThread());
-  DCHECK(data);
-  base::AutoLock lock(data_mutex_);
-  *data = wifi_data_;
-  // If we've successfully completed a scan, indicate that we have all of the
-  // data we can get.
-  return is_first_scan_complete_;
-}
-
-// Thread implementation
-void WifiDataProviderCommon::Init() {
+void WifiDataProviderCommon::StartDataProvider() {
   DCHECK(wlan_api_ == NULL);
   wlan_api_.reset(NewWlanApi());
   if (wlan_api_ == NULL) {
     // Error! Can't do scans, so don't try and schedule one.
     is_first_scan_complete_ = true;
     return;
   }
 
   DCHECK(polling_policy_ == NULL);
   polling_policy_.reset(NewPollingPolicy());
   DCHECK(polling_policy_ != NULL);
 
   // Perform first scan ASAP regardless of the polling policy. If this scan
   // fails we'll retry at a rate in line with the polling policy.
   ScheduleNextScan(0);
 }
 
-void WifiDataProviderCommon::CleanUp() {
-  // Destroy these instances in the thread on which they were created.
+void WifiDataProviderCommon::StopDataProvider() {
   wlan_api_.reset();
   polling_policy_.reset();
 }
 
+bool WifiDataProviderCommon::GetData(WifiData* data) {
+  DCHECK(data);

[bulach, 2013/08/13 16:59:46]

nit: no need, a null-ptr dereference below would be as clear as this DCHECK.

[Michael van Ouwerkerk, 2013/08/13 17:44:30]

Done.

+  *data = wifi_data_;
+  // If we've successfully completed a scan, indicate that we have all of the
+  // data we can get.
+  return is_first_scan_complete_;
+}
+
 void WifiDataProviderCommon::DoWifiScanTask() {
   bool update_available = false;
   WifiData new_data;
   if (!wlan_api_->GetAccessPointData(&new_data.access_point_data)) {
     ScheduleNextScan(polling_policy_->NoWifiInterval());
   } else {
-    {
-      base::AutoLock lock(data_mutex_);
-      update_available = wifi_data_.DiffersSignificantly(new_data);
-      wifi_data_ = new_data;
-    }
+    update_available = wifi_data_.DiffersSignificantly(new_data);
+    wifi_data_ = new_data;
     polling_policy_->UpdatePollingInterval(update_available);
     ScheduleNextScan(polling_policy_->PollingInterval());
   }
   if (update_available || !is_first_scan_complete_) {
     is_first_scan_complete_ = true;
     NotifyListeners();
   }
 }
 
 void WifiDataProviderCommon::ScheduleNextScan(int interval) {
-  message_loop()->PostDelayedTask(
+  client_loop()->PostDelayedTask(
       FROM_HERE,
       base::Bind(&WifiDataProviderCommon::DoWifiScanTask,
                  weak_factory_.GetWeakPtr()),
       base::TimeDelta::FromMilliseconds(interval));
 }
 
 }  // namespace content