Upgrade WX to r74856, mainly to support @2x.

Externals/wxWidgets3/include/wx/webviewfshandler.h

@@ -0,0 +1,37 @@
+/////////////////////////////////////////////////////////////////////////////
+// Name:        webviewfshandler.h
+// Purpose:     Custom webview handler for virtual file system
+// Author:      Nick Matthews
+// Copyright:   (c) 2012 Steven Lamerton
+// Licence:     wxWindows licence
+/////////////////////////////////////////////////////////////////////////////
+
+// Based on webviewarchivehandler.h file by Steven Lamerton
+
+#ifndef _WX_WEBVIEW_FS_HANDLER_H_
+#define _WX_WEBVIEW_FS_HANDLER_H_
+
+#include "wx/setup.h"
+
+#if wxUSE_WEBVIEW
+
+class wxFSFile;
+class wxFileSystem;
+
+#include "wx/webview.h"
+
+//Loads from uris such as scheme:example.html
+
+class WXDLLIMPEXP_WEBVIEW wxWebViewFSHandler : public wxWebViewHandler
+{
+public:
+    wxWebViewFSHandler(const wxString& scheme);
+    virtual ~wxWebViewFSHandler();
+    virtual wxFSFile* GetFile(const wxString &uri);
+private:
+    wxFileSystem* m_fileSystem;
+};
+
+#endif // wxUSE_WEBVIEW
+
+#endif // _WX_WEBVIEW_FS_HANDLER_H_