Implement the AES GCM cipher suites for TLS.

The AES GCM cipher suites are disabled in DTLS. This will be fixed soon.

Disable the HMAC-SHA256 cipher suites so that our ClientHello doesn't
become too big.

Patch by Adam Langley.

R=agl@chromium.org,rsleevi@chromium.org
BUG=255241
TEST=none

Review URL: https://chromiumcodereview.appspot.com/21696002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@217716 0039d316-1c4b-4281-b951-d872f2087c98
14 files changed