Fix use of up and down arrows when the candidate window is not visible.

src/IBusChewingEngine.gob

Index: src/IBusChewingEngine.gob
diff --git a/src/IBusChewingEngine.gob b/src/IBusChewingEngine.gob
index 339ca3eca46ac25b2a660a5e942d05068faaf537..0fe13accbc30a008963a1f574db1edabc68bf9d1 100644
--- a/src/IBusChewingEngine.gob
+++ b/src/IBusChewingEngine.gob
@@ -941,21 +941,29 @@ class IBus:Chewing:Engine from IBus:Engine{
     override (IBus:Engine) void
     cursor_up(IBus:Engine *engine){
 	Self *self=SELF(engine);
-	//chewing_handle_Up(self->context);
-	self_cursor_prev(self);
-	self_update(self);
-	ibus_lookup_table_set_cursor_pos(self->table, self->tableCursor);
-	ibus_engine_update_lookup_table(IBUS_ENGINE(self),self->table,TRUE);
+	if (self->tableVisible){
+	    self_cursor_prev(self);
+	    self_update(self);
+	    ibus_lookup_table_set_cursor_pos(self->table, self->tableCursor);
+	    ibus_engine_update_lookup_table(IBUS_ENGINE(self),self->table,TRUE);
+	} else {
+	    chewing_handle_Up(self->context);
+	    self_update(self);
+	}
     }
 
     override (IBus:Engine) void
     cursor_down(IBus:Engine *engine){
 	Self *self=SELF(engine);
-	//chewing_handle_Down(self->context);
-	self_cursor_next(self);
-	self_update(self);
-	ibus_lookup_table_set_cursor_pos(self->table, self->tableCursor);
-	ibus_engine_update_lookup_table(IBUS_ENGINE(self),self->table,TRUE);
+	if (self->tableVisible){
+	    self_cursor_next(self);
+	    self_update(self);
+	    ibus_lookup_table_set_cursor_pos(self->table, self->tableCursor);
+	    ibus_engine_update_lookup_table(IBUS_ENGINE(self),self->table,TRUE);
+	} else {
+	    chewing_handle_Down(self->context);
+	    self_update(self);
+	}
     }
 
     override (IBus:Engine) void