Please describe the problem:
If, in a callback function connected to the "changed", a user sets 
the "selected region" via gtk_editable_select_region(), the selection is lost 
if the trigger for the "change" had been a text insertion. On a deletion, 
however, the selection is not lost, but is correctly kept.



Steps to reproduce:
1.
attach the following function to the "changed" signal of a GTK_ENTRY

 void changed_text_handler(GtkEditable *editable, gpointer data)
{
    gchar *text;
    text = gtk_editable_get_chars(editable, 0, -1);
    if (!strcmp(text, "ABC"))
          gtk_editable_select_region(editable, 1, 3);
    g_free(text);
}

2. type  "ABC"  into the GTK_ENTRY (omit  the ")
3. (nothing is selected...)
4. type  "D"  , then backspace (deleting the D)
 


Actual results:
after backspacing, the "BC" are  selected. 

Expected results:
the "BC" should have been selected immediately after typing the "C"

Does this happen every time?
yes

Other information:
i traced the bug to the  gtk_entry_enter_text()  function.
Before the call to gtk_entry_set_position_internal(), we should check if
selection bounds have been set.  the following patch works

FIX <> BUG
2753,2754c2753
< if (!gtk_editable_get_selection_bounds (editable, NULL, NULL))  /*ZS FIX */ 
<      gtk_entry_set_position_internal (entry, tmp_pos, FALSE);
---
>   gtk_entry_set_position_internal (entry, tmp_pos, FALSE);