Update NSS to 3.38

- Added HACL*Poly1305 32-bit (INRIA/Microsoft)
- Updated to final TLS 1.3 draft version (28)
- Removed TLS 1.3 prerelease draft limit check
- Removed NPN code
- Enabled dev/urandom-only RNG on Linux with NSS_SEED_ONLY_DEV_URANDOM for non-standard environments
- Fixed several bugs with TLS 1.3 negotiation
- Updated internal certificate store
- Added support for the TLS Record Size Limit Extension.
- Fixed CVE-2018-0495
- Various security fixes in the ASN.1 code.

security/nss/automation/taskcluster/scripts/gen_coverage_report.sh

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+
+source $(dirname "$0")/tools.sh
+
+# Clone NSPR.
+hg_clone https://hg.mozilla.org/projects/nspr ./nspr default
+
+out=/home/worker/artifacts
+mkdir -p $out
+
+# Generate coverage report.
+cd nss && ./mach coverage --outdir=$out ssl_gtests