[recipes] Clarify a function name

[Matthias Clasen <matthiasc src gnome org>]

commit 7442c7540a78c4ec32ed0cb2abec44fb17cd1d93
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Feb 6 07:49:43 2017 +0100

    Clarify a function name
    
    This is about the default image, not the default button.

 src/gr-edit-page.c |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)
---
diff --git a/src/gr-edit-page.c b/src/gr-edit-page.c
index 715ca33..16fbc3f 100644
--- a/src/gr-edit-page.c
+++ b/src/gr-edit-page.c
@@ -185,7 +185,7 @@ update_image_button_sensitivity (GrEditPage *page)
 }
 
 static void
-update_default_button (GrEditPage *page)
+update_default_image_button (GrEditPage *page)
 {
         int index;
 
@@ -217,13 +217,13 @@ images_changed (GrEditPage *page)
 {
         update_image_button_sensitivity (page);
         populate_image_flowbox (page);
-        update_default_button (page);
+        update_default_image_button (page);
 }
 
 static void
 index_changed (GrEditPage *page)
 {
-        update_default_button (page);
+        update_default_image_button (page);
 }
 
 static void
@@ -1903,10 +1903,10 @@ gr_edit_page_edit (GrEditPage *page,
 
         if (recipe) {
                 page->index_handler_id = g_signal_connect_swapped (recipe, "notify::default-image",
-                                                                   G_CALLBACK (update_default_button), page);
+                                                                   G_CALLBACK (update_default_image_button), 
page);
         }
 
-        update_default_button (page);
+        update_default_image_button (page);
 }
 
 static void