Remove implicit conversions from scoped_refptr to T* in mojo/

mojo/system/data_pipe_producer_dispatcher.cc

Index: mojo/system/data_pipe_producer_dispatcher.cc
diff --git a/mojo/system/data_pipe_producer_dispatcher.cc b/mojo/system/data_pipe_producer_dispatcher.cc
index df9ea336542ace6bded507a8cfc25f4c2cc3232d..3850f1af6babf86b7f30138af268cbb65de0008a 100644
--- a/mojo/system/data_pipe_producer_dispatcher.cc
+++ b/mojo/system/data_pipe_producer_dispatcher.cc
@@ -15,7 +15,7 @@ DataPipeProducerDispatcher::DataPipeProducerDispatcher() {
 }
 
 void DataPipeProducerDispatcher::Init(scoped_refptr<DataPipe> data_pipe) {
-  DCHECK(data_pipe);
+  DCHECK(data_pipe.get());
   data_pipe_ = data_pipe;
 }
 
@@ -25,7 +25,7 @@ Dispatcher::Type DataPipeProducerDispatcher::GetType() const {
 
 DataPipeProducerDispatcher::~DataPipeProducerDispatcher() {
   // |Close()|/|CloseImplNoLock()| should have taken care of the pipe.
-  DCHECK(!data_pipe_);
+  DCHECK(!data_pipe_.get());
 }
 
 void DataPipeProducerDispatcher::CancelAllWaitersNoLock() {