net: remove leftover post-quantum feature.

This was left over from r702570. I'll probably add it back next week
when reenabling this (hopefully for the last time), but best to clean it
up just in case.

Change-Id: Ic2b0b447ed6b88eade3585fe91076965e72e373f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1895382
Commit-Queue: Adam Langley <agl@chromium.org>
Commit-Queue: David Benjamin <davidben@chromium.org>
Auto-Submit: Adam Langley <agl@chromium.org>
Reviewed-by: David Benjamin <davidben@chromium.org>
Cr-Commit-Position: refs/heads/master@{#711772}

net/base/features.cc

@@ -39,9 +39,6 @@ const base::Feature kPartitionSSLSessionsByNetworkIsolationKey{
 const base::Feature kTLS13KeyUpdate{"TLS13KeyUpdate",
                                     base::FEATURE_DISABLED_BY_DEFAULT};
 
-const base::Feature kPostQuantumCECPQ2{"PostQuantumCECPQ2",
-                                       base::FEATURE_DISABLED_BY_DEFAULT};
-
 const base::Feature kNetUnusedIdleSocketTimeout{
     "NetUnusedIdleSocketTimeout", base::FEATURE_DISABLED_BY_DEFAULT};
 

net/base/features.h

@@ -57,9 +57,6 @@ NET_EXPORT extern const base::Feature
 // servers.
 NET_EXPORT extern const base::Feature kTLS13KeyUpdate;
 
-// Enables CECPQ2, a post-quantum key-agreement, in TLS 1.3 connections.
-NET_EXPORT extern const base::Feature kPostQuantumCECPQ2;
-
 // Changes the timeout after which unused sockets idle sockets are cleaned up.
 NET_EXPORT extern const base::Feature kNetUnusedIdleSocketTimeout;