Remove the deprecated use_nss and USE_NSS flags.

build/config/BUILD.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/allocator.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//build/module_args/v8.gni")
 
@@ skipping 108 matching lines @@
   }
   if (use_glib) {
     defines += [ "USE_GLIB=1" ]
   }
   if (use_openssl) {
     defines += [ "USE_OPENSSL=1" ]
     if (use_openssl_certs) {
       defines += [ "USE_OPENSSL_CERTS=1" ]
     }
   } else if (use_nss_certs) {
-    defines += [
-      "USE_NSS_CERTS=1",
-
-      # TODO(davidben): USE_NSS is a deprecated alias for USE_NSS_CERTS and will
-      # be removed. See https://crbug.com/462040.
-      "USE_NSS=1",
-    ]
+    defines += [ "USE_NSS_CERTS=1" ]
   }
   if (use_ozone) {
     defines += [ "USE_OZONE=1" ]
   }
   if (use_x11) {
     defines += [ "USE_X11=1" ]
   }
   if (use_allocator != "tcmalloc") {
     defines += [ "NO_TCMALLOC" ]
   }
@@ skipping 188 matching lines @@
       "CoreFoundation.framework",
       "CoreGraphics.framework",
       "CoreText.framework",
       "Foundation.framework",
       "UIKit.framework",
     ]
   } else if (is_linux) {
     libs = [ "dl" ]
   }
 }