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

components/cryptauth/bluetooth_throttler_impl.cc

Index: components/cryptauth/bluetooth_throttler_impl.cc
diff --git a/components/cryptauth/bluetooth_throttler_impl.cc b/components/cryptauth/bluetooth_throttler_impl.cc
index d72337ef5936650a6cdadd8a73261892114af8e3..239528a863230b56e369e234bc32cd0e239350a0 100644
--- a/components/cryptauth/bluetooth_throttler_impl.cc
+++ b/components/cryptauth/bluetooth_throttler_impl.cc
@@ -6,7 +6,9 @@
 
 #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"
 
@@ -18,6 +20,14 @@ 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)) {}