Try to reland v8_snapshot GN build changes, take #3

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) {
@@ skipping 593 matching lines @@
   ]
 
   args = rebase_path(outputs, root_build_dir) +
          rebase_path(sources, root_build_dir)
 }
 
 action("run_mksnapshot") {
   visibility = [ ":*" ]  # Only targets in this file can depend on this.
 
   deps = [
-    ":mksnapshot($snapshot_toolchain)",
+    ":mksnapshot($v8_snapshot_toolchain)",
   ]
 
   script = "tools/run.py"
 
   outputs = [
     "$target_gen_dir/snapshot.cc",
   ]
 
   args = [
-    "./" + rebase_path(get_label_info(":mksnapshot($snapshot_toolchain)",
+    "./" + rebase_path(get_label_info(":mksnapshot($v8_snapshot_toolchain)",
                                       "root_out_dir") + "/mksnapshot",
                        root_build_dir),
     "--startup_src",
     rebase_path("$target_gen_dir/snapshot.cc", root_build_dir),
   ]
 
   if (v8_random_seed != "0") {
     args += [
       "--random-seed",
       v8_random_seed,
@@ skipping 1358 matching lines @@
 
   public_deps = [
     ":v8_libplatform",
   ]
 }
 
 ###############################################################################
 # Executables
 #
 
-if (current_toolchain == snapshot_toolchain) {
+if (current_toolchain == v8_snapshot_toolchain) {
   executable("mksnapshot") {
     visibility = [ ":*" ]  # Only targets in this file can depend on this.
 
     sources = [
       "src/snapshot/mksnapshot.cc",
     ]
 
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [ "//build/config/compiler:no_chromium_code" ]
     configs += [
@@ skipping 81 matching lines @@
   }
 
   if (!is_component_build) {
     sources += [ "$target_gen_dir/d8-js.cc" ]
   }
   if (v8_enable_i18n_support) {
     deps += [ "//third_party/icu" ]
   }
 }
 
-if ((current_toolchain == host_toolchain && v8_toolset_for_shell == "host") || (current_toolchain == snapshot_toolchain && v8_toolset_for_shell == "host") || (current_toolchain != host_toolchain && v8_toolset_for_shell == "target")) {
+if ((current_toolchain == host_toolchain && v8_toolset_for_shell == "host") || (current_toolchain == v8_snapshot_toolchain && v8_toolset_for_shell == "host") || (current_toolchain != host_toolchain && v8_toolset_for_shell == "target")) {
   executable("v8_shell") {
     sources = [
       "samples/shell.cc",
     ]
 
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [ "//build/config/compiler:no_chromium_code" ]
     configs += [
       # Note: don't use :internal_config here because this target will get
       # the :external_config applied to it by virtue of depending on :v8, and
@@ skipping 68 matching lines @@
   sources = [
     "test/fuzzer/wasm-asmjs.cc",
   ]
 
   deps = [
     ":fuzzer_support",
   ]
 
   configs = [ ":internal_config" ]
 }