Remove libcurl support from update_engine_sideload.
While sideloading an update from recovery we don't need nor want to
download payload from HTTP(S) URLs, only local file:// are supported.
This patch moves libcurl_http_fetcher and certificate_checker files out
of libpayload_consumer dropping the libcurl and libssl dependencies from
it and the update_engine_sideload.
Bug: 27178350
TEST=build UE for Brillo and Android. Unittests still pass and
update_engine_sideload doesn't link to libcurl.
(cherry picked from commit 14c0da88a93aa7b1aa71d5e7e923b537f0d419f3)
Change-Id: I6195fc0a8ceedfc7fd1a92bdd0acc55ace2c1232
17 files changed
