[Fuchsia] Fix test image creation

BUILD.gn

 # Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 # This target will be built if no target is specified when invoking ninja.
 group("default") {
   if (is_fuchsia || is_fuchsia_host) {
     # Fuchsia has run_vm_tests marked testonly.
     testonly = true
   }
@@ skipping 100 matching lines @@
     ":create_sdk",
   ]
 }
 
 group("samples") {
   deps = [
     "runtime/bin:sample_extension",
   ]
 }
 
-# The rules below build a qemu Fuchsia OS image that includes the Dart tree
-# under /system/test/dart. Building this image is gated by the GN argument
-# 'dart_build_fuchsia_test_image' because building the image is slow.
+# The rules below build a Fuchsia OS image that includes the Dart tree
+# under /system/test/dart.
 if (is_fuchsia) {
   declare_args() {
     dart_build_fuchsia_test_image = false
   }
 
   action("generate_dart_test_manifest") {
     testonly = true
 
     deps = [
       "//packages/gn:mkbootfs",
     ]
 
     output_prefix = "$target_gen_dir/dart_test_tree"
     outputs = [
       "$output_prefix.manifest",
     ]
 
     mode = "release"
     if (is_debug) {
       mode = "debug"
     }
 
     mkbootfs_gen = get_label_info("//packages/gn:mkbootfs", "target_gen_dir")
-    user_manifest = "$mkbootfs_gen/user.bootfs.manifest"
+    system_manifest = "$mkbootfs_gen/system.bootfs.manifest"
 
     script = "tools/gen_fuchsia_test_manifest.py"
     args = [
       "-m",
       mode,
       "-u",
-      rebase_path(user_manifest),
+      rebase_path(system_manifest),
       "-o",
       rebase_path(output_prefix),
     ]
   }
 
   action("generate_dart_test_image") {
     testonly = true
     deps = [
       ":generate_dart_test_manifest",
       "runtime/bin:dart",
       "runtime/bin:process_test",
       "runtime/bin:run_vm_tests",
     ]
 
+    mkbootfs_gen = get_label_info("//packages/gn:mkbootfs", "target_gen_dir")
+    boot_manifest = "$mkbootfs_gen/boot.bootfs.manifest"
+
     # Compute path to magenta bootdata.bin
     if (current_cpu == "arm64") {
       magenta_bootdata =
           "//out/build-magenta/build-magenta-qemu-arm64/bootdata.bin"
     } else if (current_cpu == "x64") {
       magenta_bootdata =
           "//out/build-magenta/build-magenta-pc-x86-64/bootdata.bin"
     } else {
       assert(false, "unable to determine path to magenta's bootdata.bin")
     }
 
     input = "$target_gen_dir/dart_test_tree.manifest"
     inputs = [
       magenta_bootdata,
       input,
     ]
 
     output = "$root_out_dir/dart_test_tree.bin"
     outputs = [
       output,
     ]
 
     script = "//packages/gn/make_bootfs.py"
     args = [
-      "--manifest",
+      "--boot-manifest",
+      rebase_path(boot_manifest),
+      "--system-manifest",
       rebase_path(input),
       "--output-file",
       rebase_path(output),
       "--build-id-map",
       rebase_path("$target_gen_dir/build_id_map"),
       "--pre-binaries",
       rebase_path(magenta_bootdata),
     ]
   }
 }