Add GetNativeHandle() to wxWebSession and wxWebRequest

This allows to retrieve the handles used internally in order to do
something not supported by the public API yet.

include/wx/webrequest.h

@@ -45,6 +45,9 @@ class wxWebResponse;
 class wxWebSession;
 class wxWebSessionFactory;
 
+typedef struct wxWebRequestHandleOpaque* wxWebRequestHandle;
+typedef struct wxWebSessionHandleOpaque* wxWebSessionHandle;
+
 class wxWebAuthChallengeImpl;
 class wxWebRequestImpl;
 class wxWebResponseImpl;
@@ -183,6 +186,8 @@ public:
 
     wxFileOffset GetBytesExpectedToReceive() const;
 
+    wxWebRequestHandle GetNativeHandle() const;
+
 private:
     // Ctor is only used by wxWebSession.
     friend class wxWebSession;
@@ -230,6 +235,8 @@ public:
 
     void Close();
 
+    wxWebSessionHandle GetNativeHandle() const;
+
 private:
     static void RegisterFactory(const wxString& backend,
                                 wxWebSessionFactory* factory);