Defer loading of audio/video tags while prerendering.

net/tools/testserver/testserver.py

Index: net/tools/testserver/testserver.py
diff --git a/net/tools/testserver/testserver.py b/net/tools/testserver/testserver.py
index 59975c72a8ac7e2038381a4c613a87ebc870ded4..0d4a4308fff1689040c0e32f9ab54f59744b9dc1 100755
--- a/net/tools/testserver/testserver.py
+++ b/net/tools/testserver/testserver.py
@@ -934,11 +934,14 @@ class TestPageHandler(BasePageHandler):
 
       range = self.headers.get('Range')
       if range and range.startswith('bytes='):
-        # Note this doesn't handle all valid byte range values (i.e. open ended
-        # ones), just enough for what we needed so far.
+        # Note this doesn't handle all valid byte range values (i.e. left
+        # open ended ones), just enough for what we needed so far.
         range = range[6:].split('-')
         start = int(range[0])
-        end = int(range[1])
+        if range[1]:
+          end = int(range[1])
+        else:
+          end = len(data)
 
         self.send_response(206)
         content_range = 'bytes ' + str(start) + '-' + str(end) + '/' + \