Add support for icons in wxAUI panes title bars.

Add wxAuiPaneInfo::Icon() method and shows its use in the sample.

Closes #12856.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66670 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/aui/framemanager.h

@@ -570,6 +570,17 @@ public:
     */
     wxAuiPaneInfo& Hide();
 
+    /**
+        Icon() sets the icon of the pane.
+
+        Notice that the height of the icon should be smaller than the value
+        returned by wxAuiDockArt::GetMetric(wxAUI_DOCKART_CAPTION_SIZE) to
+        ensure that it appears correctly.
+
+        @since 2.9.2
+    */
+    wxAuiPaneInfo& Icon(const wxBitmap& b);
+
     /**
         IsBottomDockable() returns @true if the pane can be docked at the bottom of the
         managed frame.