Don't use a version script when linking libpdf.so

pdf/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.
 
 pdf_engine = 0  # 0 PDFium
 
 # TODO(GYP) need support for loadable modules
 shared_library("pdf") {
   sources = [
     "button.h",
@@ skipping 70 matching lines @@
     #  'mac_real_dsym': 1,
     #},
     #'sources+': [
     #  'Info.plist'
     #]
     #'xcode_settings': {
     #  'INFOPLIST_FILE': 'Info.plist',
     #},
   }
 
-  if (is_linux) {
-    # TODO(GYP)
-    ## Use a custom version script to prevent leaking the vendor name in
-    ## visible symbols.
-    #'ldflags': [
-    #  '-Wl,--version-script=<!(cd <(DEPTH) && pwd -P)/pdf/libpdf.map'
-    #],
-  }
-
   deps = [
     "//base",
     "//net",
     "//ppapi:ppapi_cpp",
     "//third_party/pdfium",
   ]
 }
 
 # TODO(GYP) pdf_linux_symbols target.