[vala/0.38] girparser: Allow change of parameter names

[Rico Tzschichholz <ricotz src gnome org>]

commit 77ef31cb4d120e93ab2cdf3e825dae0e50a7ef0a
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Sat Dec 2 18:31:03 2017 +0100

    girparser: Allow change of parameter names

 vala/valagirparser.vala |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)
---
diff --git a/vala/valagirparser.vala b/vala/valagirparser.vala
index 1be2c94..9d471f0 100644
--- a/vala/valagirparser.vala
+++ b/vala/valagirparser.vala
@@ -2434,7 +2434,10 @@ public class Vala.GirParser : CodeVisitor {
                        Report.error (get_current_src (), "expected start element of `parameter' or 
`instance-parameter'");
                }
                start_element (element_type);
-               string name = reader.get_attribute ("name");
+               var name = metadata.get_string (ArgumentType.NAME);
+               if (name == null) {
+                       name = reader.get_attribute ("name");
+               }
                if (name == null) {
                        name = default_name;
                }