net: don't always add TLS padding.

net/third_party/nss/README.chromium

 Name: Network Security Services (NSS)
 URL: http://www.mozilla.org/projects/security/pki/nss/
 Version: 3.15.5 Beta 2
 Security Critical: Yes
 License: MPL 2
 License File: NOT_SHIPPED
 
 This directory includes a copy of NSS's libssl from the hg repo at:
   https://hg.mozilla.org/projects/nss
 
@@ skipping 57 matching lines @@
     patches/aesgcmchromium.patch
 
   * Support ChaCha20+Poly1305 ciphersuites
     http://tools.ietf.org/html/draft-agl-tls-chacha20poly1305-01
     patches/chacha20poly1305.patch
 
   * Fix session cache lock creation race.
     patches/cachelocks.patch
     https://bugzilla.mozilla.org/show_bug.cgi?id=764646
 
-  * Always add an extension to a ClientHello to make it 512 bytes.
-    patches/paddingextensionall.patch
-
   * Support the Certificate Transparency (RFC 6962) TLS extension
     signed_certificate_timestamp (client only).
     patches/signedcertificatetimestamps.patch
     https://bugzilla.mozilla.org/show_bug.cgi?id=944175
 
   * Add a function to allow the cipher suites preference order to be set.
     patches/cipherorder.patch
 
   * Add TLS_FALLBACK_SCSV cipher suite to version fallback connections.
     patches/fallbackscsv.patch
@@ skipping 11 matching lines @@
   * Use NSSRWLock instead of PRRWLock in sslSessionID. This avoids the bugs
     in the lock rank checking code in PRRWLock.
     patches/nssrwlock.patch
     https://bugzilla.mozilla.org/show_bug.cgi?id=957812
 
 Apply the patches to NSS by running the patches/applypatches.sh script.  Read
 the comments at the top of patches/applypatches.sh for instructions.
 
 The ssl/bodge directory contains files taken from the NSS repo that we required
 for building libssl outside of its usual build environment.