AI 147991: make sources appear in online-pdk/guide
  BUG=1815368

Automated import of CL 147991
diff --git a/pdk/hosting/pdk.py b/pdk/hosting/pdk.py
index 421f195..a1c7c07 100644
--- a/pdk/hosting/pdk.py
+++ b/pdk/hosting/pdk.py
@@ -26,7 +26,7 @@
 
 class MainPage(webapp.RequestHandler):
   def get(self):
-    self.redirect('online-pdk/index.html')
+    self.redirect('online-pdk/guide/index.html')
 
 application = webapp.WSGIApplication([('/', MainPage)], debug=True)