Previous code led to much code duplication. For DMS, each method redefining
'index_html' had to merge all possible parameters (with their default values)
of overridden methods. This was even worse for DocumentProxyMixin.index_html,
because the type of the proxied document is not even known.

This commit adds a new 'fill_args_from_request' decorator and fixes
'index_html' for proxied images (default value for 'frame' was only changed
in Image class).

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@35905 20353a03-c40f-0410-a6d1-a30d3c3de9de