use ChangeValue instead of SetValue to avoid bogus EVT_TEXT events

when just setting the descriptive text.
(ported from 2.8 branch)


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@44390 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/srchctlg.cpp

@@ -123,7 +123,7 @@ public:
     {
         if ( GetValue() == m_descriptiveText )
         {
-            SetValue(wxEmptyString);
+            ChangeValue(wxEmptyString);
         }
         
         m_descriptiveText = text;
@@ -163,7 +163,7 @@ protected:
     {
         if ( IsEmpty() && !(wxWindow::FindFocus() == this) )
         {
-            SetValue(m_descriptiveText);
+            ChangeValue(m_descriptiveText);
             SetInsertionPoint(0);
             SetForegroundColour(wxStepColour(m_defaultFG, LIGHT_STEP));
         }
@@ -174,7 +174,7 @@ protected:
         event.Skip();
         if ( GetValue() == m_descriptiveText )
         {
-            SetValue(wxEmptyString);
+            ChangeValue(wxEmptyString);
             SetForegroundColour(m_defaultFG);
         }
     }