Add v8_external_startup_data GN rule

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/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/mips.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 
+if (is_android) {
+  import("//build/config/android/rules.gni")
+}
+
 # Because standalone V8 builds are not supported, assume this is part of a
 # Chromium build.
 import("//build/module_args/v8.gni")
 
 import("snapshot_toolchain.gni")
 
 # TODO(jochen): These will need to be user-settable to support standalone V8
 # builds.
 v8_deprecation_warnings = false
 v8_enable_disassembler = false
@@ skipping 380 matching lines @@
   ]
 
   outputs = [
     "$target_gen_dir/d8-js.cc",
   ]
 
   args = rebase_path(outputs, root_build_dir) + [ "D8" ] +
          rebase_path(inputs, root_build_dir)
 }
 
+if (is_android) {
+  android_assets("v8_external_startup_data_assets") {
+    if (v8_use_external_startup_data) {
+      deps = [
+        "//v8",
+      ]
+      sources = [
+        "$root_out_dir/natives_blob.bin",
+        "$root_out_dir/snapshot_blob.bin",
+      ]
+      disable_compression = true
+    }
+  }
+}
+
 if (v8_use_external_startup_data) {
   action("natives_blob") {
     visibility = [ ":*" ]  # Only targets in this file can depend on this.
 
     deps = [
       ":js2c",
       ":js2c_code_stubs",
       ":js2c_experimental",
       ":js2c_extras",
       ":js2c_experimental_extras",
@@ skipping 1395 matching lines @@
     if (!is_component_build) {
       sources += [
         "$target_gen_dir/d8-js.cc",
       ]
     }
     if (v8_enable_i18n_support) {
       deps += [ "//third_party/icu" ]
     }
   }
 }