WifiDataProviderChromeOs: Call NetworkHandler from correct task runner.

device/geolocation/wifi_data_provider_chromeos.cc

Index: device/geolocation/wifi_data_provider_chromeos.cc
diff --git a/device/geolocation/wifi_data_provider_chromeos.cc b/device/geolocation/wifi_data_provider_chromeos.cc
index aef72ae3758e120d044dffd04b63b34731e43536..c8bbbf347b45c9a0ad2cff2ebf309a07854f1155 100644
--- a/device/geolocation/wifi_data_provider_chromeos.cc
+++ b/device/geolocation/wifi_data_provider_chromeos.cc
@@ -9,12 +9,13 @@
 #include <stdint.h>
 
 #include "base/bind.h"
-#include "base/single_thread_task_runner.h"
 #include "base/strings/utf_string_conversions.h"
-#include "base/threading/thread_task_runner_handle.h"
 #include "chromeos/network/geolocation_handler.h"
+#include "chromeos/network/network_handler.h"
 #include "device/geolocation/wifi_data_provider_manager.h"
 
+using chromeos::NetworkHandler;
+
 namespace device {
 
 namespace {
@@ -28,16 +29,14 @@ const int kNoWifiPollingIntervalMilliseconds = 20 * 1000;            // 20s
 }  // namespace
 
 WifiDataProviderChromeOs::WifiDataProviderChromeOs()
-    : started_(false),
-      is_first_scan_complete_(false),
-      main_task_runner_(base::ThreadTaskRunnerHandle::Get()) {}
+    : started_(false), is_first_scan_complete_(false) {}
 
 WifiDataProviderChromeOs::~WifiDataProviderChromeOs() {}
 
 void WifiDataProviderChromeOs::StartDataProvider() {
   DCHECK(CalledOnClientThread());
 
-  DCHECK(polling_policy_ == NULL);
+  DCHECK(polling_policy_ == nullptr);
   polling_policy_.reset(
       new GenericWifiPollingPolicy<kDefaultPollingIntervalMilliseconds,
                                    kNoChangePollingIntervalMilliseconds,
@@ -61,14 +60,7 @@ bool WifiDataProviderChromeOs::GetData(WifiData* data) {
   return is_first_scan_complete_;
 }
 
-void WifiDataProviderChromeOs::DoStartTaskOnUIThread() {
-  CHECK(main_task_runner_->BelongsToCurrentThread());
-  DoWifiScanTaskOnUIThread();
-}
-
-void WifiDataProviderChromeOs::DoWifiScanTaskOnUIThread() {
-  CHECK(main_task_runner_->BelongsToCurrentThread());
-
+void WifiDataProviderChromeOs::DoWifiScanTaskOnNetworkHandlerThread() {
   // This method could be scheduled after a ScheduleStop.
   if (!started_)
     return;
@@ -89,7 +81,7 @@ void WifiDataProviderChromeOs::DoWifiScanTaskOnUIThread() {
 void WifiDataProviderChromeOs::DidWifiScanTaskNoResults() {
   DCHECK(CalledOnClientThread());
   // Schedule next scan if started (StopDataProvider could have been called
-  // in between DoWifiScanTaskOnUIThread and this method).
+  // in between DoWifiScanTaskOnNetworkHandlerThread and this method).
   if (started_)
     ScheduleNextScan(polling_policy_->NoWifiInterval());
 }
@@ -99,7 +91,7 @@ void WifiDataProviderChromeOs::DidWifiScanTask(const WifiData& new_data) {
   bool update_available = wifi_data_.DiffersSignificantly(new_data);
   wifi_data_ = new_data;
   // Schedule next scan if started (StopDataProvider could have been called
-  // in between DoWifiScanTaskOnUIThread and this method).
+  // in between DoWifiScanTaskOnNetworkHandlerThread and this method).
   if (started_) {
     polling_policy_->UpdatePollingInterval(update_available);
     ScheduleNextScan(polling_policy_->PollingInterval());
@@ -114,9 +106,15 @@ void WifiDataProviderChromeOs::DidWifiScanTask(const WifiData& new_data) {
 void WifiDataProviderChromeOs::ScheduleNextScan(int interval) {
   DCHECK(CalledOnClientThread());
   DCHECK(started_);
-  main_task_runner_->PostDelayedTask(
+  if (!NetworkHandler::IsInitialized()) {
+    LOG(ERROR) << "ScheduleNextScan called with uninitialized NetworkHandler";
+    return;
+  }
+  NetworkHandler::Get()->task_runner()->PostDelayedTask(
       FROM_HERE,
-      base::Bind(&WifiDataProviderChromeOs::DoWifiScanTaskOnUIThread, this),
+      base::Bind(
+          &WifiDataProviderChromeOs::DoWifiScanTaskOnNetworkHandlerThread,
+          this),
       base::TimeDelta::FromMilliseconds(interval));
 }
 
@@ -129,23 +127,31 @@ void WifiDataProviderChromeOs::ScheduleStop() {
 void WifiDataProviderChromeOs::ScheduleStart() {
   DCHECK(CalledOnClientThread());
   DCHECK(!started_);
+  if (!NetworkHandler::IsInitialized()) {
+    LOG(ERROR) << "ScheduleStart called with uninitialized NetworkHandler";
+    return;
+  }
   started_ = true;
   // 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.
-  main_task_runner_->PostTask(
+  NetworkHandler::Get()->task_runner()->PostTask(
       FROM_HERE,
-      base::Bind(&WifiDataProviderChromeOs::DoStartTaskOnUIThread, this));
+      base::Bind(
+          &WifiDataProviderChromeOs::DoWifiScanTaskOnNetworkHandlerThread,
+          this));
 }
 
 bool WifiDataProviderChromeOs::GetAccessPointData(
     WifiData::AccessPointDataSet* result) {
-  // If in startup or shutdown, chromeos::NetworkHandler is uninitialized.
-  if (!chromeos::NetworkHandler::IsInitialized())
+  // If in startup or shutdown, NetworkHandler is uninitialized.
+  if (!NetworkHandler::IsInitialized())
     return false;  // Data not ready.
 
+  DCHECK(NetworkHandler::Get()->task_runner()->BelongsToCurrentThread());
+
   // If wifi isn't enabled, we've effectively completed the task.
   chromeos::GeolocationHandler* const geolocation_handler =
-      chromeos::NetworkHandler::Get()->geolocation_handler();
+      NetworkHandler::Get()->geolocation_handler();
   if (!geolocation_handler || !geolocation_handler->wifi_enabled())
     return true;  // Access point list is empty, no more data.