Revert of Convert //net and //chromecast to std::unordered_*

net/base/network_change_notifier_linux.cc

Index: net/base/network_change_notifier_linux.cc
diff --git a/net/base/network_change_notifier_linux.cc b/net/base/network_change_notifier_linux.cc
index 69bab1d4482452bca281b26d1f18e18a3799f6c4..b18b6c21c2421be7bb83e475583ae19299cc1a45 100644
--- a/net/base/network_change_notifier_linux.cc
+++ b/net/base/network_change_notifier_linux.cc
@@ -15,7 +15,7 @@
 
 class NetworkChangeNotifierLinux::Thread : public base::Thread {
  public:
-  explicit Thread(const std::unordered_set<std::string>& ignored_interfaces);
+  explicit Thread(const base::hash_set<std::string>& ignored_interfaces);
   ~Thread() override;
 
   // Plumbing for NetworkChangeNotifier::GetCurrentConnectionType.
@@ -45,7 +45,7 @@
 };
 
 NetworkChangeNotifierLinux::Thread::Thread(
-    const std::unordered_set<std::string>& ignored_interfaces)
+    const base::hash_set<std::string>& ignored_interfaces)
     : base::Thread("NetworkChangeNotifier"),
       address_tracker_(new internal::AddressTrackerLinux(
           base::Bind(&NetworkChangeNotifierLinux::Thread::OnIPAddressChanged,
@@ -95,7 +95,7 @@
 }
 
 NetworkChangeNotifierLinux::NetworkChangeNotifierLinux(
-    const std::unordered_set<std::string>& ignored_interfaces)
+    const base::hash_set<std::string>& ignored_interfaces)
     : NetworkChangeNotifier(NetworkChangeCalculatorParamsLinux()),
       notifier_thread_(new Thread(ignored_interfaces)) {
   // We create this notifier thread because the notification implementation