Don't change wxTextEntry value if it didn't really change.

This is not only unnecessary but also can result in a kind of infinite loop
when wxTextEntry::SetValue() is called from wxEVT_IDLE handler as really
modifying the text results in another wxEVT_IDLE being generated and another
call to SetValue() and so on while not doing it in the first place completely
works around the problem and is also more efficient.

Closes #13936.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@71308 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/textentrycmn.cpp

@@ -223,11 +223,20 @@ void wxTextEntryBase::AppendText(const wxString& text)
 }
 
 void wxTextEntryBase::DoSetValue(const wxString& value, int flags)
+{
+    if ( value != GetValue() )
     {
         EventsSuppressor noeventsIf(this, !(flags & SetValue_SendEvent));
 
         SelectAll();
         WriteText(value);
+    }
+    else // Same value, no need to do anything.
+    {
+        // Except that we still need to generate the event for consistency with
+        // the normal case when the text does change.
+        SendTextUpdatedEvent(GetEditableWindow());
+    }
 
     SetInsertionPoint(0);
 }