Remove implicit conversions from scoped_refptr to T* in device/

This patch was generated by running the rewrite_scoped_refptr clang tool
on a Windows build.

BUG=110610

Review URL: https://codereview.chromium.org/720973002

Cr-Commit-Position: refs/heads/master@{#303940}

device/bluetooth/bluetooth_adapter_win.cc

@@ -46,7 +46,7 @@ BluetoothAdapterWin::BluetoothAdapterWin(const InitCallback& init_callback)
 }
 
 BluetoothAdapterWin::~BluetoothAdapterWin() {
-  if (task_manager_) {
+  if (task_manager_.get()) {
     task_manager_->RemoveObserver(this);
     task_manager_->Shutdown();
   }