[gtk/constraint-guide-3] Remove stray variable unref() in ConstraintSolver

[Emmanuele Bassi <ebassi src gnome org>]

commit b236cab3baa9ee87b27521c6386cb102faabab42
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Fri Jun 28 14:22:53 2019 +0100

    Remove stray variable unref() in ConstraintSolver
    
    The marker variables table does not acquire a reference on the
    constraint variables it contains, as they are part of the constraint
    used as the key, and will be released when the constraint is removed.

 gtk/gtkconstraintsolver.c | 2 --
 1 file changed, 2 deletions(-)
---
diff --git a/gtk/gtkconstraintsolver.c b/gtk/gtkconstraintsolver.c
index 22fa0111a4..ce25aca56e 100644
--- a/gtk/gtkconstraintsolver.c
+++ b/gtk/gtkconstraintsolver.c
@@ -944,8 +944,6 @@ gtk_constraint_solver_new_expression (GtkConstraintSolver *self,
 
           gtk_constraint_expression_set_variable (expr, dummy_var, 1.0);
           g_hash_table_insert (self->marker_vars, constraint, dummy_var);
-
-          gtk_constraint_variable_unref (dummy_var);
         }
       else
         {