Delete Cronet Data Reduction Proxy integration

components/cronet/ios/BUILD.gn

 # Copyright 2015 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/buildflag_header.gni")
 import("//build/config/ios/rules.gni")
 import("//build/config/mac/symbols.gni")
 import("//build/mac/tweak_info_plist.gni")
 import("//build/util/process_version.gni")
 import("//build/util/version.gni")
 import("//components/grpc_support/include/headers.gni")
 import("//testing/test.gni")
 import("//url/features.gni")
 
 assert(!is_component_build, "Cronet requires static library build.")
 
-declare_args() {
-  cronet_enable_data_reduction_proxy_support = false
-}
-
 process_version("cronet_version_header") {
   template_file = "//components/cronet/version.h.in"
   sources = [
     "//chrome/VERSION",
   ]
   output = "$target_gen_dir/version.h"
   extra_args = [
     "-e",
     "VERSION_FULL=\"%s.%s.%s.%s\" % (MAJOR,MINOR,BUILD,PATCH)",
   ]
@@ skipping 175 matching lines @@
   }
 
   group("cronet_package") {
     deps = [
       ":cronet_dsym_archive",
       ":cronet_package_copy",
       ":generate_license",
     ]
   }
 }