__FUNCTION__ cannot concatenate with constant strings in all compilers.

win8/test/ui_automation_client.cc

Index: win8/test/ui_automation_client.cc
diff --git a/win8/test/ui_automation_client.cc b/win8/test/ui_automation_client.cc
index 6af9bc402ef59f29c546287d79a63d8764fbdf96..153b917bd6a921347251b425cec1c3cea2b855a6 100644
--- a/win8/test/ui_automation_client.cc
+++ b/win8/test/ui_automation_client.cc
@@ -321,7 +321,7 @@ void UIAutomationClient::Context::HandleWindowOpen(
   }
 
   if (V_VT(&var) != VT_BSTR) {
-    LOG(ERROR) << __FUNCTION__ " class name is not a BSTR: " << V_VT(&var);
+    LOG(ERROR) << __FUNCTION__ << " class name is not a BSTR: " << V_VT(&var);
     return;
   }