Impacted versions: 8-11

## Current behavior:

If during an XMLRPC call you try to get anything from `http.request`, you'd get a `RuntimeError` such as this one:

```
Traceback (most recent call last):
  File "/opt/odoo/custom/src/odoo/odoo/service/wsgi_server.py", line 56, in xmlrpc_return
    result = odoo.http.dispatch_rpc(service, method, params)
  File "/opt/odoo/custom/src/odoo/odoo/http.py", line 118, in dispatch_rpc
    result = dispatch(method, params)
  File "/opt/odoo/custom/src/odoo/odoo/service/common.py", line 57, in dispatch
    return g[exp_method_name](*params)
  [...]
  File "/usr/local/lib/python2.7/dist-packages/werkzeug/local.py", line 343, in __getattr__
    return getattr(self._get_current_object(), name)
  File "/usr/local/lib/python2.7/dist-packages/werkzeug/local.py", line 302, in _get_current_object
    return self.__local()
  File "/usr/local/lib/python2.7/dist-packages/werkzeug/local.py", line 135, in _lookup
    raise RuntimeError(\'object unbound\')
RuntimeError: object unbound
```

This renders imposible in practice to fix issues such as https://github.com/OCA/server-tools/issues/1125 or to implement https://github.com/odoo/odoo/pull/22212#issuecomment-380425764.

## Expected behavior:

XML-RPC calls should have request, since after all they belong to one. Otherwise, at least there should be an alternate way to access the request parameters.

Fix for v12: https://github.com/odoo/odoo/pull/24187

@Tecnativa
"""Decorator marking the decorated method as being a handler for
    requests. The method must be part of a subclass of ``Controller``.
    :param route: string or array. The route part that will determine which
                  http requests will match the decorated method. Can be a
                  single string or an array of strings. See werkzeug's routing
                  documentation for the format of route expression (
                  http://werkzeug.pocoo.org/docs/routing/ ).
    :param type: The type of request, can be ``'http'`` or ``'json'``.
    :param auth: The type of authentication method, can on of the following:
                 * ``user``: The user must be authenticated and the current request
                   will perform using the rights of the user.
                 * ``public``: The user may or may not be authenticated. If she isn't,
                   the current request will perform using the shared Public user.
                 * ``none``: The method is always active, even if there is no
                   database. Mainly used by the framework and authentication
                   modules. There request code will not have any facilities to access
                   the database nor have any configuration indicating the current
                   database nor the current user.
    :param methods: A sequence of http methods this route applies to. If not
                    specified, all methods are allowed.
    :param cors: The Access-Control-Allow-Origin cors directive value.
    :param bool csrf: Whether CSRF protection should be enabled for the route.
                      Defaults to ``True``. See :ref:`CSRF Protection
                      <csrf>` for more.
    .. _csrf:
    .. admonition:: CSRF Protection
        :class: alert-warning
        .. versionadded:: 9.0