Change defaults for build args to accommodate Flutter and Fuchsia.

sdk/BUILD.gn

 # Copyright (c) 2017, 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 GN file contains build rules for assembling the Dart SDK. There are
 # two possible variants: the "Full" SDK, and the "Platform" SDK. If you want
 # to make a new subset of the Full SDK, make it the same way we make
 # the Platform SDK.
 #
 # Warning:
 # If you need to copy something into dart-sdk/lib/foo in addition to the stuff
 # copied there by :copy_libraries, then you must depend on ":copy_libraries",
 # or ":copy_libraries" may delete/overwrite your addition, and the build will
 # fail.
 
 import("../build/copy_tree.gni")
 
 declare_args() {
   # Build a SDK with less stuff. It excludes dart2js, ddc, and web libraries.
-  dart_platform_sdk = false
-}
-
-if (is_fuchsia ||
-    is_fuchsia_host ||
-    current_cpu == "arm64" ||
-    current_cpu == "arm") {
   dart_platform_sdk = true
+  # Path to stripped dart binary relative to build output directory.
+  dart_stripped_binary = "dart"
 }
 
 # The directory layout of the SDK is as follows:
 #
 # ..dart-sdk/
 # ....bin/
 # ......dart or dart.exe (executable)
 # ......dart.lib (import library for VM native extensions on Windows)
 # ......dartdoc
 # ......dartfmt
@@ skipping 181 matching lines @@
 copy("copy_dart") {
   visibility = [ ":create_common_sdk" ]
   deps = [
     "../runtime/bin:dart",
   ]
   dart_out = get_label_info("../runtime/bin:dart", "root_out_dir")
   if (is_win) {
     sources = [
       "$dart_out/dart.exe",
     ]
-  } else if (is_fuchsia || is_fuchsia_host) {
-    sources = [
-      "$dart_out/dart",
-    ]
   } else {
     sources = [
-      "$dart_out/exe.stripped/dart",
+      "$dart_out/$dart_stripped_binary"
     ]
   }
   if (is_win) {
     sources += [ "$dart_out/dart.lib" ]
   }
   outputs = [
     "$root_out_dir/dart-sdk/bin/{{source_file_part}}",
   ]
 }
 
@@ skipping 537 matching lines @@
 group("create_sdk") {
   deps = [
     ":create_common_sdk",
   ]
   if (dart_platform_sdk) {
     deps += [ ":create_platform_sdk" ]
   } else {
     deps += [ ":create_full_sdk" ]
   }
 }