Convert //chromecast from scoped_ptr to std::unique_ptr

chromecast/media/base/cast_media_default.cc

Index: chromecast/media/base/cast_media_default.cc
diff --git a/chromecast/media/base/cast_media_default.cc b/chromecast/media/base/cast_media_default.cc
index dbf486736d88611ec61cb76a185dd32836f10ae7..aca34451170a784d6823e13c9375527635db751b 100644
--- a/chromecast/media/base/cast_media_default.cc
+++ b/chromecast/media/base/cast_media_default.cc
@@ -2,10 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "base/memory/scoped_ptr.h"
-#include "build/build_config.h"
+#include <memory>
+
 #include "base/single_thread_task_runner.h"
 #include "base/thread_task_runner_handle.h"
+#include "build/build_config.h"
 #include "chromecast/base/task_runner_impl.h"
 #include "chromecast/media/cma/backend/media_pipeline_backend_default.h"
 #include "chromecast/public/cast_media_shlib.h"