- Supports only primitive xpcshell HTTP requests which don't set/get HTTP
headers, don't do redirects, observers, load groups, or anything else other
than basic things like looking at the reply body, Content-type, Content-length, etc.
- Tested with network/test/unit_ipc/test_simple_wrap.js (patch @ bug 521922)
- Only used if "NECKO_E10S_HTTP" set in environment.
- Force http.h to get #included before any IPDL files, to centralize #define
handling of LOG and to make sure FORCE_PR_LOGGING is set if needed (bug
545995)