Mojo: Fix incorrect PLOG in raw_channel_win.cc.

mojo/system/raw_channel_win.cc

Index: mojo/system/raw_channel_win.cc
diff --git a/mojo/system/raw_channel_win.cc b/mojo/system/raw_channel_win.cc
index 8568e8e7317e3a000784d7b48173b2e44cc5a76b..4837837ebc720efd7aab91df79fd31ba21d9ae0e 100644
--- a/mojo/system/raw_channel_win.cc
+++ b/mojo/system/raw_channel_win.cc
@@ -298,7 +298,8 @@ void RawChannelWin::RawChannelIOHandler::OnReadCompleted(DWORD bytes_read,
 
   if (error != ERROR_SUCCESS) {
     DCHECK_EQ(bytes_read, 0u);
-    PLOG_IF(ERROR, error != ERROR_BROKEN_PIPE) << "ReadFile";
+    LOG_IF(ERROR, error != ERROR_BROKEN_PIPE)
+        << "ReadFile: " << logging::SystemErrorCodeToString(error);
     owner_->OnReadCompleted(false, 0);
   } else {
     DCHECK_GT(bytes_read, 0u);