Add util function to see if a given phase should be run.

kdesrc-build

@@ -895,6 +895,13 @@ my $run_mode = 'build'; # Determines if updating, building, installing, etc.
         push @{$self}, $phase unless list_has([@{$self}], $phase);
     }
 
+    # Returns true if the given phase name is present in this list.
+    sub has
+    {
+        my ($self, $phase) = @_;
+        return grep { $_ eq $phase } (@{$self});
+    }
+
     # Get/sets number of phases depending on whether any are passed in.
     sub phases
     {