Remove crypto::ECPrivateKey::IsSupported.

Remove crypto::ECPrivateKey::IsSupported.

We no longer need to worry about the system NSS on decrepit Linux
distributions. The only platform where ECPrivateKey is backed by NSS is iOS and
we control that one.

BUG=519504
Committed: https://crrev.com/24bb5a4b2e4d909c27740c5a12b3e167c49329f2
Cr-Commit-Position: refs/heads/master@{#354379}

[davidben, 2015-10-15 20:17:43]

davidben@chromium.org changed reviewers:
+ rsleevi@chromium.org

[Ryan Sleevi, 2015-10-15 22:00:16]

LGTM, although we may have to end up re-introducing some of this code if Token
Binding team succeeds in convincing Chrome-security to support hardware backed
tokens (although I sincerely hope it doesn't happen)

https://codereview.chromium.org/1408813002/diff/1/net/socket/ssl_client_socke...
File net/socket/ssl_client_socket.cc (right):

https://codereview.chromium.org/1408813002/diff/1/net/socket/ssl_client_socke...
net/socket/ssl_client_socket.cc:136: // CLIENT_NO_ECC is unused now.
This doesn't match how CLIENT_BAD_SYSTEM_TIME was handled (see lines 137-138)

Either way, they should be kept in sync; I'd be fine nuking line 138

[davidben, 2015-10-15 22:03:00]

The CQ bit was checked by davidben@chromium.org

[commit-bot: I haz the power, 2015-10-15 22:05:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1408813002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1408813002/1

[commit-bot: I haz the power, 2015-10-15 22:13:30]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-15 22:14:38]

Patchset 1 (id:??) landed as
https://crrev.com/24bb5a4b2e4d909c27740c5a12b3e167c49329f2
Cr-Commit-Position: refs/heads/master@{#354379}