Reland "Remove HttpStreamFactory interface."

Reland https://crrev.com/c/1000487.

Remove HttpStreamFactory interface, also rename HttpStreamFactoryImpl to
HttpStreamFactory.

Bug: 829429
Change-Id: I298879817785174d1d7290520f889f0252074e14
Reviewed-on: https://chromium-review.googlesource.com/1023321
Commit-Queue: Bence Béky <bnc@chromium.org>
Reviewed-by: Ryan Hamilton <rch@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#553180}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: ea3e3f22b07a492c2211a035af9081fe6ec170c9
25 files changed