Allow an app to cut down start time by not doing unnecessary mime types initialisation

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@54356 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/changes.txt

@@ -98,9 +98,14 @@ All (Unix):
 
 - MIME types reading fixed when running under GNOME, reading .desktop
   files and also the default application list.
+- Added filesys.no-mimetypesmanager system option so that applications that
+  must load an XRC file at program startup don't have to incur the
+  mime types manager initialization penalty.
 
 wxMSW:
 
+- Compile fix for WinCE in window.cpp (no VkKeyScan in Windows CE).
+
 wxGTK:
 
 wxMac:

src/common/filesys.cpp

@@ -23,6 +23,7 @@
     #include "wx/module.h"
 #endif
 
+#include "wx/sysopt.h"
 #include "wx/wfstream.h"
 #include "wx/mimetype.h"
 #include "wx/filename.h"
@@ -62,6 +63,16 @@ wxString wxFileSystemHandler::GetMimeTypeFromExt(const wxString& location)
 
 #if wxUSE_MIMETYPE
     static bool s_MinimalMimeEnsured = false;
+
+    // Don't use mime types manager if the application doesn't need it and it would be
+    // cause an unacceptable delay, especially on startup.
+    bool useMimeTypesManager = true;
+#if wxUSE_SYSTEM_OPTIONS
+    useMimeTypesManager = (wxSystemOptions::GetOptionInt(wxT("filesys.no-mimetypesmanager")) == 0);
+#endif
+
+    if (useMimeTypesManager)
+    {
         if (!s_MinimalMimeEnsured)
         {
             static const wxFileTypeInfo fallbacks[] =
@@ -107,7 +118,10 @@ wxString wxFileSystemHandler::GetMimeTypeFromExt(const wxString& location)
         delete ft;
         
         return mime;
-#else
+    }
+    else
+#endif
+    {
         if ( ext.IsSameAs(wxT("htm"), false) || ext.IsSameAs(_T("html"), false) )
             return wxT("text/html");
         if ( ext.IsSameAs(wxT("jpg"), false) || ext.IsSameAs(_T("jpeg"), false) )
@@ -119,7 +133,7 @@ wxString wxFileSystemHandler::GetMimeTypeFromExt(const wxString& location)
         if ( ext.IsSameAs(wxT("bmp"), false) )
             return wxT("image/bmp");
         return wxEmptyString;
-#endif
+    }
 }