[epiphany] encoding-dialog: Placate -Wdiscarded-qualifiers

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 46ee95ba2bacbb5106bbaf1e652ab04fdd25dd6b
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Sun Jan 24 22:11:45 2016 -0600

    encoding-dialog: Placate -Wdiscarded-qualifiers

 src/ephy-encoding-dialog.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/ephy-encoding-dialog.c b/src/ephy-encoding-dialog.c
index 8a6a5f5..aa09285 100644
--- a/src/ephy-encoding-dialog.c
+++ b/src/ephy-encoding-dialog.c
@@ -316,8 +316,8 @@ sort_list_store (gconstpointer a,
                  gconstpointer b,
                  gpointer user_data)
 {
-       const char *encoding1 = ephy_encoding_get_title_elided (EPHY_ENCODING (a));
-       const char *encoding2 = ephy_encoding_get_title_elided (EPHY_ENCODING (b));
+       const char *encoding1 = ephy_encoding_get_title_elided ((EphyEncoding *)a);
+       const char *encoding2 = ephy_encoding_get_title_elided ((EphyEncoding *)b);
 
        return g_strcmp0 (encoding1, encoding2);
 }