Convert //extensions/browser/api from scoped_ptr to std::unique_ptr

extensions/browser/api/serial/serial_api.cc

Index: extensions/browser/api/serial/serial_api.cc
diff --git a/extensions/browser/api/serial/serial_api.cc b/extensions/browser/api/serial/serial_api.cc
index 74346baa2f52cb6e7d00f1ebf7a40e2488d58ee8..3f126a80046cd9c1b675b27880e2e797368402b9 100644
--- a/extensions/browser/api/serial/serial_api.cc
+++ b/extensions/browser/api/serial/serial_api.cc
@@ -43,7 +43,7 @@ const char kErrorSerialConnectionNotFound[] = "Serial connection not found.";
 const char kErrorGetControlSignalsFailed[] = "Failed to get control signals.";
 
 template <class T>
-void SetDefaultScopedPtrValue(scoped_ptr<T>& ptr, const T& value) {
+void SetDefaultScopedPtrValue(std::unique_ptr<T>& ptr, const T& value) {
   if (!ptr.get())
     ptr.reset(new T(value));
 }
@@ -86,7 +86,7 @@ bool SerialGetDevicesFunction::Prepare() {
 void SerialGetDevicesFunction::Work() {
   DCHECK_CURRENTLY_ON(BrowserThread::FILE);
 
-  scoped_ptr<device::SerialDeviceEnumerator> enumerator =
+  std::unique_ptr<device::SerialDeviceEnumerator> enumerator =
       device::SerialDeviceEnumerator::Create();
   mojo::Array<device::serial::DeviceInfoPtr> devices = enumerator->GetDevices();
   results_ = serial::GetDevices::Results::Create(