[glib] Implement g_content_type_is_mime_type() (clone of win32's)

[Patrick Griffis <pgriffis src gnome org>]

commit ea586b47a306a1e9b5edd6fc94eb872342a87024
Author: Daniel Macks <dmacks netspace org>
Date:   Mon Apr 24 01:52:27 2017 -0400

    Implement g_content_type_is_mime_type() (clone of win32's)
    
    Add missing function, copying from gcontenttype-win32.c per Patrick
    Griffis (Comment #55 of bug report)
    
    https://bugzilla.gnome.org/show_bug.cgi?id=734946

 gio/gosxcontenttype.c |   17 +++++++++++++++++
 1 files changed, 17 insertions(+), 0 deletions(-)
---
diff --git a/gio/gosxcontenttype.c b/gio/gosxcontenttype.c
index 3c223d6..8c15ec7 100644
--- a/gio/gosxcontenttype.c
+++ b/gio/gosxcontenttype.c
@@ -133,6 +133,23 @@ g_content_type_is_a (const gchar *ctype,
 }
 
 gboolean
+g_content_type_is_mime_type (const gchar *type,
+                             const gchar *mime_type)
+{
+  gchar *content_type;
+  gboolean ret;
+
+  g_return_val_if_fail (type != NULL, FALSE);
+  g_return_val_if_fail (mime_type != NULL, FALSE);
+
+  content_type = g_content_type_from_mime_type (mime_type);
+  ret = g_content_type_is_a (type, content_type);
+  g_free (content_type);
+
+  return ret;
+}
+
+gboolean
 g_content_type_is_unknown (const gchar *type)
 {
   g_return_val_if_fail (type != NULL, FALSE);