[Sync] Make chrome sync response compression as default

sync/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/features.gni")
 import("//sync/protocol/protocol_sources.gni")
 import("//testing/test.gni")
 
 component("sync") {
   public_deps = [
@@ skipping 707 matching lines @@
     "//net",
     "//net:test_support",
     "//sql",
     "//sql:test_support",
     "//sync",
     "//sync/protocol",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/leveldatabase",
     "//third_party/protobuf:protobuf_lite",
-    "//third_party/zlib",
   ]
 
   if (is_chromeos) {
     # Required by get_session_name_unittest.cc on Chrome OS.
     deps += [ "//chromeos" ]
   }
 
   if (is_ios) {
     sources -= [ "internal_api/http_bridge_unittest.cc" ]
   }
@@ skipping 152 matching lines @@
       ":fake_server_jni",
       ":sync_core",
       ":test_support_sync_fake_server",
       "//base",
       "//sync/protocol:protocol",
       "//testing/gtest",
       "//url:url",
     ]
   }
 }