Upload/Download dart_snapshotter

mojo/public/tools/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/module_args/mojo.gni")
 import("../mojo.gni")
 
 if (mojo_use_prebuilt_mojo_shell) {
   copy("copy_mojo_shell") {
     filename = "mojo_shell"
@@ skipping 10 matching lines @@
       sources = [
         "prebuilt/shell/linux-x64/$filename",
       ]
       outputs = [
         "$root_out_dir/$filename",
       ]
     }
   }
 }
 
+if (mojo_use_prebuilt_dart_snapshotter) {
+  copy("copy_dart_snapshotter") {
+    if (host_os == "linux") {
+      platform = "linux-x64"
+    } else if (host_os == "mac") {
+      platform = "mac-x64"
+    } else {
+      assert(false, "$host_os not supported")
+    }
+    sources = [
+      "prebuilt/dart_snapshotter/$platform/dart_snapshotter",
+    ]
+    outputs = [
+      "$root_out_dir/dart_snapshotter",
+    ]
+  }
+}
+
 if (mojo_use_prebuilt_network_service) {
   copy("copy_network_service") {
     filename = "network_service.mojo"
     if (defined(mojo_prebuilt_network_service_location) &&
         mojo_prebuilt_network_service_location != "") {
       sources = [
         "$mojo_prebuilt_network_service_location",
       ]
     } else {
       if (is_android) {
@@ skipping 50 matching lines @@
 if (mojo_use_dart_apptest_framework) {
   copy("dart_apptest_framework") {
     sources = [
       "prebuilt/frameworks/apptest.dartzip",
     ]
     outputs = [
       "$target_out_dir/dart_apptest_framework.dartzip",
     ]
   }
 }