[gnome-maps] osmEditDialog: Add translation context to "Add to OpenStreetMap"

[Piotr Drąg <piotrdrag src gnome org>]

commit 019048359bcbe47e2c59fa7d073123ea30a7d4af
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Sun Feb 14 18:00:56 2016 +0100

    osmEditDialog: Add translation context to "Add to OpenStreetMap"
    
    It's needed to disambiguate the string: a menu element and a window
    title must be translated differently in many languages.

 src/osmEditDialog.js |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/osmEditDialog.js b/src/osmEditDialog.js
index bdc496f..006ec0a 100644
--- a/src/osmEditDialog.js
+++ b/src/osmEditDialog.js
@@ -214,7 +214,7 @@ const OSMEditDialog = new Lang.Class({
         this._typeButton.connect('clicked', this._onTypeClicked.bind(this));
 
         if (this._addLocation) {
-            this._headerBar.title = _("Add to OpenStreetMap");
+            this._headerBar.title = C_("dialog title", "Add to OpenStreetMap");
             this._typeLabel.visible = true;
             this._typeButton.visible = true;