try v8

android_webview/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/config/android/config.gni")
 import("//build/config/android/rules.gni")
 import("//build/config/locales.gni")
 import("//tools/grit/repack.gni")
 import("system_webview_apk_tmpl.gni")
 import("webview_repack_locales.gni")
@@ skipping 356 matching lines @@
   ]
 }
 
 shared_library("libwebviewchromium") {
   deps = [
     ":webview_entry_point",
   ]
   configs -= [ "//build/config/android:hide_native_jni_exports" ]
 }
 
-if (defined(webview_only_libmonochrome) && webview_only_libmonochrome) {
+if (android_64bit_target_cpu) {
   shared_library("monochrome") {
     deps = [
       ":webview_entry_point",
     ]
     configs -= [ "//build/config/android:hide_native_jni_exports" ]
   }
 }
 
 source_set("common") {
   sources = [
@@ skipping 360 matching lines @@
     android_manifest = get_target_outputs(":system_webview_manifest")
     android_manifest = android_manifest[1]
     android_manifest_dep = ":system_webview_manifest"
     deps = [
       ":system_webview_resources",
       "//android_webview/glue",
     ]
     apk_name = "SystemWebView"
   }
 }