Add native wxSearchCtrl for GTK+ port

include/wx/srchctrl.h

@@ -16,12 +16,7 @@
 
 #include "wx/textctrl.h"
 
-#if !defined(__WXUNIVERSAL__) && defined(__WXMAC__)
-    // search control was introduced in Mac OS X 10.3 Panther
-    #define wxUSE_NATIVE_SEARCH_CONTROL 1
-
-    #define wxSearchCtrlBaseBaseClass wxTextCtrl
-#else
+#if (!defined(__WXMAC__) && !defined(__WXGTK20__)) || defined(__WXUNIVERSAL__)
     // no native version, use the generic one
     #define wxUSE_NATIVE_SEARCH_CONTROL 0
 
@@ -33,6 +28,17 @@
           public wxTextCtrlIface
     {
     };
+#elif defined(__WXMAC__)
+    // search control was introduced in Mac OS X 10.3 Panther
+    #define wxUSE_NATIVE_SEARCH_CONTROL 1
+
+    #define wxSearchCtrlBaseBaseClass wxTextCtrl
+#elif defined(__WXGTK20__)
+    // Use GtkSearchEntry if available, construct a similar one using GtkEntry
+    // otherwise.
+    #define wxUSE_NATIVE_SEARCH_CONTROL 1
+
+    #define wxSearchCtrlBaseBaseClass wxTextCtrlBase
 #endif
 
 // ----------------------------------------------------------------------------
@@ -81,6 +87,8 @@ private:
 #if wxUSE_NATIVE_SEARCH_CONTROL
     #if defined(__WXMAC__)
         #include "wx/osx/srchctrl.h"
+    #elif defined(__WXGTK__)
+        #include "wx/gtk/srchctrl.h"
     #endif
 #else
     #include "wx/generic/srchctlg.h"