[CrOS Tether] Make BluetoothThrottler a singleton which can be easily shared between EasyUnlock and…

components/cryptauth/bluetooth_throttler_impl.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 "components/cryptauth/bluetooth_throttler_impl.h"
 
 #include <utility>
 
+#include "base/memory/ptr_util.h"
 #include "base/stl_util.h"
+#include "base/time/default_tick_clock.h"
 #include "base/time/tick_clock.h"
 #include "components/cryptauth/connection.h"
 
 namespace cryptauth {
 namespace {
 
 // Time to wait after disconnect before reconnecting.
 const int kCooldownTimeSecs = 7;
 
 }  // namespace
 
+// static
+BluetoothThrottlerImpl* BluetoothThrottlerImpl::GetInstance() {
+  return base::Singleton<BluetoothThrottlerImpl>::get();
+}
+
+BluetoothThrottlerImpl::BluetoothThrottlerImpl()
+    : BluetoothThrottlerImpl(base::MakeUnique<base::DefaultTickClock>()) {}
+
 BluetoothThrottlerImpl::BluetoothThrottlerImpl(
     std::unique_ptr<base::TickClock> clock)
     : clock_(std::move(clock)) {}
 
 BluetoothThrottlerImpl::~BluetoothThrottlerImpl() {
   for (Connection* connection : connections_) {
     connection->RemoveObserver(this);
   }
 }
 
@@ skipping 26 matching lines @@
     Connection::Status new_status) {
   DCHECK(base::ContainsKey(connections_, connection));
   if (new_status == Connection::DISCONNECTED) {
     last_disconnect_time_ = clock_->NowTicks();
     connection->RemoveObserver(this);
     connections_.erase(connection);
   }
 }
 
 }  // namespace cryptauth