Add wxRibbonBar::DeletePage() and ClearPages() methods.

Also add a trivial GetPageCount() helper.

Closes #14437.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@71888 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/ribbon/bar.h

@@ -206,14 +206,38 @@ public:
     */
     wxRibbonPage* GetPage(int n);
     
+    /**
+        Get the number of pages in this bar.
+
+        @since 2.9.4
+    */
+    size_t GetPageCount() const;
+
     /**
         Dismiss the expanded panel of the currently active page.
         
-        Calls and returns the value fromwxRibbonPage::DismissExpandedPanel()
+        Calls and returns the value from wxRibbonPage::DismissExpandedPanel()
         for the currently active page, or @false if there is no active page.
     */
     bool DismissExpandedPanel();
 
+    /**
+        Delete a single page from this ribbon bar.
+
+        The user must call wxRibbonBar::Realize() after one (or more) calls to
+        this function.
+
+        @since 2.9.4
+    */
+    void DeletePage(size_t n);
+
+    /**
+        Delete all pages from the ribbon bar.
+
+        @since 2.9.4
+    */
+    void ClearPages();
+
     /**
         Shows or hides the panel area of the ribbon bar.