This is needed for the Flutter Engine to use a prebuilt Dart SDK as in
https://github.com/flutter/engine/pull/26931. When using a prebuilt
Dart SDK, the rules producing the built SDK are directed to a
different location so that GN doesn't warn about multiple rules that
produce the same file.
TEST=locally with a flutter/engine checkout
Change-Id: I4095f379c772c63f93a1c88c7f4e44804f3a6fc7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/204760
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Zach Anderson <zra@google.com>
Such that runtime/include/internal/dart_api_dl_impl.h ends up in
include/internal/dart_api_dl_impl.h in the sdk release.
Long explanation:
https://dart-review.googlesource.com/c/sdk/+/164320 tried to recover the
folder structure but failed to do so correctly. It put
runtime/include/internal/dart_api_dl_impl.h in
include/runtime/dart_api_dl_impl.h rather than
include/internal/dart_api_dl_impl.h.
The gn copy action only supports a single `outputs` string.
https://gn.googlesource.com/gn/+/HEAD/docs/reference.md#var_outputs
This string can have 'placeholders'.
https://gn.googlesource.com/gn/+/HEAD/docs/reference.md#placeholders
The only placeholder that preserves the original folder structure,
without also nesting deeply inside folders is `source_target_relative`.
If `source_target_relative` inside sdk/BUILD.gn it starts including
`runtime/include/` in its path. So the only way to achieve the correct
copy is by doing it in runtime/include/BUILD.gn.
TEST=Manual testing, we don't have tests verifying the SDK structure.
Change-Id: I9d503626266edcdd8417f5cafb0f8ff9746f89f7
Cq-Include-Trybots: luci.dart.try:dart-sdk-linux-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/200866
Reviewed-by: Tess Strickland <sstrickl@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Zach Anderson