Ignore HTTP_PROXY during test requests

urllib2 follows http_proxy/HTTP_PROXY by default.  If a (non-local)
proxy is set and a test tries to connect to localhost:$port, it will
instead attempt to connect to $port on the proxy and (presumably) fail.

This change forces the two tests that failed in the presence of
HTTP_PROXY to connect directly.

Change-Id: Ia12c91b356f0ccebf874933ff459aa2faa190655
Merge "Ignore HTTP_PROXY during test requests"