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/cpputil/tls_parser.h

@@ -123,6 +123,7 @@ class TlsParser {
   bool Read(uint32_t* val, size_t size);
   // Reads len bytes into dest buffer, overwriting it.
   bool Read(DataBuffer* dest, size_t len);
+  bool ReadFromMark(DataBuffer* val, size_t len, size_t mark);
   // Reads bytes into dest buffer, overwriting it.  The number of bytes is
   // determined by reading from len_size bytes from the stream first.
   bool ReadVariable(DataBuffer* dest, size_t len_size);