improve diagnostics in call parsing, patch suggested by
Matthijs Kooijman

llvm-svn: 49648
diff --git a/llvm/docs/tutorial/LangImpl5.html b/llvm/docs/tutorial/LangImpl5.html
index 8081fc3..ae53fd9 100644
--- a/llvm/docs/tutorial/LangImpl5.html
+++ b/llvm/docs/tutorial/LangImpl5.html
@@ -1137,7 +1137,7 @@
       if (CurTok == ')') break;
       
       if (CurTok != ',')
-        return Error("Expected ')'");
+        return Error("Expected ')' or ',' in argument list");
       getNextToken();
     }
   }