Remove the Widevine signature files from the Linux and ChromeOS builds

third_party/widevine/cdm/BUILD.gn

 # Copyright 2014 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/chrome_build.gni")
 import("//build/config/features.gni")
 import("//chrome/process_version_rc_template.gni")
 import("//media/cdm/ppapi/cdm_paths.gni")
 import("//media/cdm/ppapi/ppapi_cdm_adapter.gni")
 import("//ppapi/features/features.gni")
 import("//third_party/widevine/cdm/widevine.gni")
 
 widevine_arch = current_cpu
 if (widevine_arch == "x86") {
   widevine_arch = "ia32"
 }
 
 widevine_cdm_binary_files = []
 widevine_cdm_manifest_file = []
 
 if (is_android) {
   # Always available on Android regardless of branding.
   widevine_cdm_version_h_file = "android/widevine_cdm_version.h"
 } else if (is_chrome_branded) {
   if (is_chromeos) {
     widevine_cdm_version_h_file =
         "chromeos/$widevine_arch/widevine_cdm_version.h"
-    widevine_cdm_binary_files = [
-      "chromeos/$widevine_arch/libwidevinecdm.so",
-      "chromeos/$widevine_arch/libwidevinecdm.so.sig",
-    ]
+    widevine_cdm_binary_files = [ "chromeos/$widevine_arch/libwidevinecdm.so" ]
   } else if (is_linux) {
     widevine_cdm_version_h_file = "linux/$widevine_arch/widevine_cdm_version.h"
-    widevine_cdm_binary_files = [
-      "linux/$widevine_arch/libwidevinecdm.so",
-      "linux/$widevine_arch/libwidevinecdm.so.sig",
-    ]
+    widevine_cdm_binary_files = [ "linux/$widevine_arch/libwidevinecdm.so" ]
   } else if (is_win) {
     widevine_cdm_version_h_file = "win/$widevine_arch/widevine_cdm_version.h"
     widevine_cdm_binary_files = [
       "win/$widevine_arch/widevinecdm.dll",
       "win/$widevine_arch/widevinecdm.dll.lib",
       "win/$widevine_arch/widevinecdm.dll.sig",
     ]
     widevine_cdm_manifest_file = [ "win/$widevine_arch/manifest.json" ]
   } else if (is_mac) {
     widevine_cdm_version_h_file = "mac/$widevine_arch/widevine_cdm_version.h"
@@ skipping 162 matching lines @@
       "../scripts/signer.py",
     ]
     outputs = [
       "$root_out_dir/installer/widevine/{{source_file_part}}",
     ]
   }
 } else {
   group("widevine_signature_scripts") {
   }
 }