chromium-bin: source true Chromium on amd64, not Chrome for Testing (inbox#284) - #414

…box#284)

The amd64 legs shipped Chrome for Testing - a *branded Google Chrome* build
governed by the Chrome ToS, which does not permit redistribution - while
declaring license_spdx BSD-3-Clause (true only of Chromium). Our public
binary cache redistributes, so this was both mislabeled and a ToS problem
(gominimal/inbox#284). Bonus drift: amd64 shipped Chrome 150.0.7871.46 while
arm64 shipped rev-1217 Chromium (147.0.7727.15) - different browser versions
per arch.

Playwright itself no longer publishes linux-x64 Chromium (its registry
fetches CfT directly for x64; verified against playwright-core 1.58/1.59
registry code - the amd64 zips are gone from cdn.playwright.dev after ~rev
1194), so the fix sources amd64 from Chromium's official snapshot bucket at
snapshot_position 1596534 - the main-branch position Chrome 147.0.7727.15
branched from (chromiumdash), i.e. the same code the arm64 build was cut
from, minus branch cherry-picks. arm64 legs unchanged.

build.sh normalizes the snapshot layouts to what Playwright's x64 registry
expects (chrome-linux -> chrome-linux64; headless-shell ->
chrome-headless-shell-linux64 + an in-dir chrome-headless-shell symlink to
headless_shell), so PLAYWRIGHT_BROWSERS_PATH discovery keeps working on both
arches. Layout logic dry-run-verified against the real zips; the amd64
runtime is exercised by this PR's build via the launch_check standalone test.

browser_version corrected to 147.0.7727.15 (a downgrade for amd64 from the
branded 150, and now truthful + arch-consistent). license_spdx BSD-3-Clause
is now accurate on both arches.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

The snapshot bucket's headless-shell.zip ships only the binary + its .paks;
headless_shell FATALs at startup on the missing icudtl.dat (caught by the PR
build's launch_check). The CfT and Playwright bundles carry the support set
inline; the snapshot build expects it beside the binary.

Fetch the full-browser chrome-linux.zip at the SAME snapshot position as an
amd64-only second source (arch-conditional array concat) and copy exactly the
support members the working Playwright arm64 bundle ships: icudtl.dat,
v8_context_snapshot.bin, and the GL/SwiftShader fallback libs. Dry-run
verified against the real zips - the final layout now matches the working
arm64 reference set file-for-file.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

…amd64

Second launch_check iteration: with ICU/v8/GL grafted the binary boots (the
remaining stderr was benign dbus noise) but --dump-dom emitted nothing. In
standalone headless, --dump-dom & friends are implemented by the command
handler loaded from headless_command_resources.pak - which NO snapshot
artifact ships. The full build rolls those resources into chrome's own
resources.pak, which is exactly why chromium-bin's launch_check passes while
headless_shell fails silently.

Borrow the pak (~3 KB of arch-independent grit resource data, same 7727
branch) from the Playwright arm64 bundle - the arm64 leg's exact artifact,
same sha256 pin - as an amd64-only extra source. Primary-zip extraction
becomes explicit per arch since the donor zip's name collides with the old
glob. Dry-run against the real zips: the amd64 bundle now has file-for-file
parity with the working arm64 reference, nothing missing.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>