Add "bundle_data" target as first step for adding bundle support to gn.

The "bundle_data" target is a type of target that has no output (just a
stamp) but list files that need to be present in any bundle that depend
on it (generally application or frameworks that link with code that use
the files at runtime) and where they should be copied into the bundle.

Design: https://docs.google.com/document/d/1bKh57hg6TSBsEmeh0zWpOO5SVGA2INu-D3FGgsyICzk/view

BUG=297668

Review URL: https://codereview.chromium.org/1751903003

Cr-Original-Commit-Position: refs/heads/master@{#379300}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: db6b992c5baaf258d1a7b9687743a93eb13ac54a
18 files changed
tree: d4b3f2ee7559c5b25bf6f78735f73ea1bb640e7a
  1. tools/