libchromeos: Remove http::GetAsString/GetAsStringAndBlock methods

These methods are of questionable utility and provide no ways
of actually checking for status code, so there is no way of telling
if the resulting string is actually a success response or an error
message.

Since using standard Get() method can provide almost the same
functionality and has the ability to check for errors using the
returned Response object, I'm deleting GetAsString... methods
as useless and dangerous.

BUG=None
TEST=`FEATURES=test emerge-link libchromeos`

Change-Id: I6ec690943bc190bcd63134415435507d1e655bab
Reviewed-on: https://chromium-review.googlesource.com/252090
Trybot-Ready: Alex Vakulenko <avakulenko@chromium.org>
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
3 files changed