Fix build removing obsolete okhttp-protocols dependency
Merge pull request #649 from unguiculus/rm_protocols

Fix build removing obsolete okhttp-protocols dependency
Don't explode if removing an absent file fails.

We still got the desired result: the file is gone. This bug has existed in
OkHttp's DiskLruCache for a long time, but it was masked by the fact that
our cleanup callable was being run with a Future, and we never asked that
Future whether it succeeded or failed. When we changed to call execute(),
the problem became unmasked.
Merge pull request #650 from square/jwilson_0314_remove_absent

Don't explode if removing an absent file fails.
fix #640: HPACK wasn't emitting header table entries to spec.
Simplify HPACK E.1.4. Indexed Header Field from Static Table
Merge pull request #652 from square/adrian.hpack-no-emitty

HPACK wasn't emitting header table entries to spec.