[FIX][web_widget_image_download] Make button look good everywhere (I hope).

Fix https://github.com/OCA/web/pull/391#issuecomment-235906320.

# Conflicts:
#	web_widget_image_download/static/src/js/web_widget_image_download.jsCopyright 2016 Jairo Llopis <jairo.llopis@tecnativa.com>

web_widget_image_download/README.rst

@@ -43,6 +43,7 @@ Contributors
 ------------
 
 * Flavio Corpa <flavio.corpa@tecnativa.com>
+* Jairo Llopis <jairo.llopis@tecnativa.com>
 
 Maintainer
 ----------

web_widget_image_download/__openerp__.py

@@ -4,7 +4,7 @@
 {
     "name": "Web Widget - Image Download",
     "summary": "Allows to download any image from its widget",
-    "version": "8.0.1.0.0",
+    "version": "8.0.1.0.1",
     "category": "web",
     "website": "https://www.tecnativa.com",
     "author": "Tecnativa, Odoo Community Association (OCA)",

web_widget_image_download/static/src/css/web_widget_image_download.css

@@ -1,6 +1,8 @@
 /* Copyright 2016 Flavio Corpa <flavio.corpa@tecnativa.com>
+ * Copyright 2016 Jairo Llopis <jairo.llopis@tecnativa.com>
  * License LGPL-3.0 or later (http://www.gnu.org/licenses/lgpl). */
 
-.openerp .oe_application a.oe_form_binary_file_download {
-  color: #eee;
+.openerp .oe_form .oe_form_field_image .oe_form_field_image_controls
+.oe_form_binary_file_download {
+    color: inherit;
 }

web_widget_image_download/static/src/js/web_widget_image_download.js

@@ -1,37 +1,39 @@
-/*
- * Copyright 2016 Flavio Corpa <flavio.corpa@tecnativa.com>
- * License LGPL-3.0 or later (http://www.gnu.org/licenses/lgpl).
- */
+/* Copyright 2016 Flavio Corpa <flavio.corpa@tecnativa.com>
+ * Copyright 2016 Jairo Llopis <jairo.llopis@tecnativa.com>
+ * License LGPL-3.0 or later (http://www.gnu.org/licenses/lgpl). */
 openerp.web_widget_image_download = function (instance) {
     'use strict';
 
     instance.web.form.web_widget_image_download = instance.web.form.FieldBinaryImage.include({
         render_value: function () {
             this._super();
-
             var $widget = this.$el.find('.oe_form_binary_file_download');
-
-            this.imgSrc = this.$el.find('img[name="image"]').attr('src');
+            this.imgSrc = this.$el.find('img[name="' + this.name + '"]')
+                .attr('src');
 
             $.ajax({
-                type: 'HEAD',
+                type: 'HEAD', // Avoid downloading full image, just headers
                 url: this.imgSrc,
                 complete: function (xhr) {
-                    // retrieve image type from server ("Content-Type" header)
-                    $widget.attr('download', xhr.getResponseHeader("Content-Type").replace('/', '.'));
+                    $widget.attr(
+                        'download',
+                        xhr.getResponseHeader("Content-Type")
+                        .replace('/', '.')
+                    );
                 }
             });
 
-            // use jquery instead of `replace` with qweb (to avoid breaking inheritance)
+            // Replace with jQuery to keep inheritance intact
             if (this.has_custom_image()) {
-                this.$el.find('.oe_form_binary_file_clear').removeClass('col-md-offset-5');
+                this.$el.find('.oe_form_binary_file_clear')
+                    .removeClass('col-md-offset-5');
             }
 
             $widget.attr('href', this.imgSrc);
         },
+
         has_custom_image: function () {
-            // check if the image of the widget is different from the default placeholder
-            return this.imgSrc && !this.imgSrc.includes('/placeholder.png');
-        }
+            return this.imgSrc != this.placeholder;
+        },
+    });
 });
-}