Update Linux to use scoped_refptr<T>::get() rather than implicit "operator T*"

content/browser/fileapi/fileapi_message_filter_unittest.cc

Index: content/browser/fileapi/fileapi_message_filter_unittest.cc
diff --git a/content/browser/fileapi/fileapi_message_filter_unittest.cc b/content/browser/fileapi/fileapi_message_filter_unittest.cc
index 98d89496b275da9c7da3f30c2cd93523d1174e9a..0a9c8fcd6cbcd82ffc286c05b5db34fefa0407c9 100644
--- a/content/browser/fileapi/fileapi_message_filter_unittest.cc
+++ b/content/browser/fileapi/fileapi_message_filter_unittest.cc
@@ -67,7 +67,7 @@ TEST_F(FileAPIMessageFilterTest, BuildEmptyBlob) {
   // channel proxy. Since OnMessageReceived is hidden on FileAPIMessageFilter,
   // cast it.
   IPC::ChannelProxy::MessageFilter* casted_filter =
-      static_cast<IPC::ChannelProxy::MessageFilter*>(filter);
+      static_cast<IPC::ChannelProxy::MessageFilter*>(filter.get());
 
   BlobHostMsg_StartBuildingBlob start_message(kUrl);
   EXPECT_TRUE(casted_filter->OnMessageReceived(start_message));