Make report_webkit thread safe by removing parser_instance attribute, as a WebkitParser instance can be shared by multiple thread and thus we don't want a thread to erase parser_instance of anorther thread.
Use NamedTemporaryFile instead of file and of deprecated mktemp. That way we ensure 2 files created at the exact same time will have a unique name
fix indentation
Fix incompatibility with Windows using tempfile.
Transmit parser_instance using partial function for mako translation callback.

This to remove parser_instance from attribute as it can cause race condition
on cursors.
Use NamedTemporaryFile instead of file and of deprecated mktemp.

That way we ensure 2 files created at the exact same time will have
a unique name