Move v8_use_external_startup_data out of //build/config:feature_flags.

ppapi/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.
 
 copy("copy_test_files") {
   visibility = [ ":*" ]
   sources = [
     # Keep "test_case.html.mock-http-headers" with "test_case.html".
     "tests/ppapi_nacl_tests_newlib.nmf",
     "tests/test_case.html",
@@ skipping 11 matching lines @@
   sources = [
     "tests/test_url_loader_data/hello.txt",
   ]
   outputs = [
     "$root_out_dir/test_url_loader_data/{{source_file_part}}",
   ]
 }
 
 import("//build/config/features.gni")
 import("//build/config/nacl/config.gni")
+import("//build_overrides/v8.gni")
 import("//ppapi/ppapi_sources.gni")
 import("//testing/test.gni")
 
 shared_library("ppapi_tests") {
   sources = ppapi_sources.test_common_source_files +
             ppapi_sources.test_trusted_source_files
 
   configs += [ "//build/config:precompiled_headers" ]
   defines = [ "GL_GLEXT_PROTOTYPES" ]
   include_dirs = [ "lib/gl/include" ]
 
   deps = [
     ":copy_test_files",
     ":copy_test_files2",
     "//build/config/sanitizers:deps",
     "//ppapi/cpp",
     "//ppapi/shared_impl",
   ]
+
+  if (v8_use_external_startup_data) {
+    configs += [ "//v8:external_startup_data" ]
+  }
 }
 
 shared_library("power_saver_test_plugin") {
   sources = [
     "tests/power_saver_test_plugin.cc",
     "tests/test_utils.cc",
   ]
 
   deps = [
     "//build/config/sanitizers:deps",
@@ skipping 293 matching lines @@
     if (target_cpu == "x86" || target_cpu == "x64") {
       data_deps += [
         ":copy_test_files",
         ":nacl_tests_copy(//build/toolchain/nacl:clang_newlib_${target_cpu})",
         ":generate_nmf(//build/toolchain/nacl:glibc_${target_cpu})",
         ":generate_nmf(//build/toolchain/nacl:newlib_pnacl)",
       ]
     }
   }
 }