Convert NaCl renderer-browser messages to mojo.

components/nacl/browser/pnacl_host.cc

Index: components/nacl/browser/pnacl_host.cc
diff --git a/components/nacl/browser/pnacl_host.cc b/components/nacl/browser/pnacl_host.cc
index 605d7d71d049fe9dd14c96765da8cbff55027f25..ecf82ef63da8b5a86e9c8a7524842fb4fb5b7a02 100644
--- a/components/nacl/browser/pnacl_host.cc
+++ b/components/nacl/browser/pnacl_host.cc
@@ -395,7 +395,7 @@ void PnaclHost::ReturnMiss(const PendingTranslationMap::iterator& entry) {
   // Return the fd
   PendingTranslation* pt = &entry->second;
   NexeFdCallback cb(pt->callback);
-  cb.Run(*pt->nexe_fd, false);
+  cb.Run(pt->nexe_fd->Duplicate(), false);
   if (!pt->nexe_fd->IsValid()) {
     // Bad FD is unrecoverable, so clear out the entry.
     pending_translations_.erase(entry);
@@ -564,7 +564,7 @@ void PnaclHost::OnBufferCopiedToTempFile(const TranslationID& id,
                                    base::Unretained(this), entry->first));
     return;
   }
-  entry->second.callback.Run(*file.get(), true);
+  entry->second.callback.Run(file->Duplicate(), true);
   BrowserThread::PostBlockingPoolTask(
       FROM_HERE,
       base::Bind(CloseScopedFile, Passed(&file)));