Revert of [gin] Unify snapshot loading on Windows and other platforms.

gin/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_overrides/v8.gni")
 import("//testing/test.gni")
 
 component("gin") {
   sources = [
     "arguments.cc",
@@ skipping 68 matching lines @@
   defines = [ "GIN_IMPLEMENTATION" ]
 
   public_deps = [
     "//base",
     "//v8",
   ]
   deps = [
     "//base/third_party/dynamic_annotations",
     "//crypto",
   ]
+  if (v8_use_external_startup_data && is_win) {
+    public_deps += [ ":gin_v8_snapshot_fingerprint" ]
+    sources += [ "$target_gen_dir/v8_snapshot_fingerprint.cc" ]
+    defines += [ "V8_VERIFY_EXTERNAL_STARTUP_DATA" ]
+  }
 
   if (is_mac) {
     libs = [ "CoreFoundation.framework" ]
   }
 
   configs += [ "//v8:external_startup_data" ]
 }
 
+if (v8_use_external_startup_data) {
+  action("gin_v8_snapshot_fingerprint") {
+    script = "//gin/fingerprint/fingerprint_v8_snapshot.py"
+
+    snapshot_file = "$root_out_dir/snapshot_blob.bin"
+    natives_file = "$root_out_dir/natives_blob.bin"
+    output_file = "$target_gen_dir/v8_snapshot_fingerprint.cc"
+
+    args = [
+      "--snapshot_file",
+      rebase_path(snapshot_file, root_build_dir),
+      "--natives_file",
+      rebase_path(natives_file, root_build_dir),
+      "--output_file",
+      rebase_path(output_file, root_build_dir),
+    ]
+    inputs = [
+      snapshot_file,
+      natives_file,
+    ]
+    outputs = [
+      output_file,
+    ]
+
+    deps = [
+      "//v8",
+    ]
+  }
+}
+
 executable("gin_shell") {
   sources = [
     "shell/gin_main.cc",
   ]
 
   deps = [
     ":gin",
     "//base",
     "//base:i18n",
     "//build/config/sanitizers:deps",
@@ skipping 62 matching lines @@
     "shell/hello_world.js",
     "test/file_unittests.js",
     "test/gtest_unittests.js",
     "../OWNERS",
   ]
 
   data_deps = [
     ":gin_shell",
   ]
 }