Adding ThreadChecker statement to d'tor for remoting/base classes

remoting/base/buffered_socket_writer.cc

Index: remoting/base/buffered_socket_writer.cc
diff --git a/remoting/base/buffered_socket_writer.cc b/remoting/base/buffered_socket_writer.cc
index f4e0b9d8c352d3de5d1c28c59037a74913ac3aaf..c5a9b7b9bcbc8384a17246e584ed2d1004d3c956 100644
--- a/remoting/base/buffered_socket_writer.cc
+++ b/remoting/base/buffered_socket_writer.cc
@@ -46,7 +46,9 @@ std::unique_ptr<BufferedSocketWriter> BufferedSocketWriter::CreateForSocket(
 
 BufferedSocketWriter::BufferedSocketWriter() : weak_factory_(this) {}
 
-BufferedSocketWriter::~BufferedSocketWriter() {}
+BufferedSocketWriter::~BufferedSocketWriter() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+}
 
 void BufferedSocketWriter::Start(
     const WriteCallback& write_callback,