IDL compiler: sync Python to r163191

Python side to:
Manage WebSQL callbacks with OwnPtr instead of refcounting
https://codereview.chromium.org/103473002/

BUG=323681
NOTRY=true
TBR=haraken

Review URL: https://codereview.chromium.org/99333007

git-svn-id: svn://svn.chromium.org/blink/trunk@163209 bbb929c8-8fbe-4397-9dbb-9b2b20218538