Re-enable HTTP/2 over NPN (for OpenSSL).

BUG=557197

Committed: https://crrev.com/0eb771aa98ba2bd4db0e2b82241afe8f5760c32e
Cr-Commit-Position: refs/heads/master@{#361053}

Review URL: https://codereview.chromium.org/1453903002

Cr-Commit-Position: refs/heads/master@{#361330}
(cherry picked from commit f4588407e26be81fda6f2507423fe42ca6d8894b)

Review URL: https://codereview.chromium.org/1488593002 .

Cr-Commit-Position: refs/branch-heads/2564@{#156}
Cr-Branched-From: 1283eca15bd9f772387f75241576cde7bdec7f54-refs/heads/master@{#359700}
5 files changed