cssvalue: Add _gtk_css_value_equal()

For now, we return FALSE for all default css values, so this is not very
useful.

I also think of this as an optimization equal, not a guaranteed equal,
because we don't even have a notion of what "equal" means.

For example, for background-repeat, "repeat, repeat" and "repeat"
are functionally equivalent. But the cssvalue has no idea that it's used
for background-repeat.
As a more complicated example, "repeat, no-repeat" and "repeat" are
equal to what one sees as long as there's only one image listed
background-image-source. But once you start transition'ing to an image
with 2 sources, it's different...

1 files changed, 1 insertions, 1 deletions

diff --git a/gtk/gtkcssstyleproperty.c b/gtk/gtkcssstyleproperty.c
index 933dbd47a5..a8bcf2f1cc 100644
--- a/gtk/gtkcssstyleproperty.c
+++ b/gtk/gtkcssstyleproperty.c
@@ -311,7 +311,7 @@ gtk_css_style_property_real_equal (GtkCssStyleProperty *property,
                                    GtkCssValue         *value1,
                                    GtkCssValue         *value2)
 {
-  return FALSE;
+  return _gtk_css_value_equal (value1, value2);
 }
 
 static void