Object GET requests with a truthy X-Newest header are not resumed if a
backend request times out. The GetOrHeadHandler therefore uses the
regular node_timeout when waiting for a backend connection response,
rather than the possibly shorter recoverable_node_timeout. However,
previously while reading data from a backend response the
recoverable_node_timeout would still be used with X-Newest requests.
This patch simplifies GetOrHeadHandler to never use
recoverable_node_timeout when X-Newest is truthy.
Change-Id: I326278ecb21465f519b281c9f6c2dedbcbb5ff14
2500fbeea9