Return a new resource handler instance to handle the request or an NULL
reference to allow default handling of the request. |browser| and |frame|
will be the browser window and frame respectively that originated the
request or NULL if the request did not originate from a browser window
(for example, if the request came from cef_urlrequest_t). The |request|
object passed to this function cannot be modified.
Return a new resource handler instance to handle the request or an NULL reference to allow default handling of the request. |browser| and |frame| will be the browser window and frame respectively that originated the request or NULL if the request did not originate from a browser window (for example, if the request came from cef_urlrequest_t). The |request| object passed to this function cannot be modified.