fix: let custom V8 snapshots reach the main process again - #52872

…52876)

fix: let custom V8 snapshots reach the main process again (#52872)

Since the main process started booting from the embedded Node.js startup
snapshot (#51703), its context is deserialized from that blob, which was
built on top of the stock snapshot_blob.bin at build time. Objects a
custom snapshot puts into the default context -- electron-mksnapshot
users, and the browser_v8_context_snapshot.bin the
loadBrowserProcessSpecificV8Snapshot fuse selects -- therefore never
showed up in the main process on native builds (mac arm64, linux x64,
win x64), while cross-built targets, which ship without the Node
snapshot, kept working. spec/fixtures/snapshot-items-available ("f is
not defined") reproduces it, but CI only ran verify-mksnapshot.py with
--create-snapshot-only since the GHA migration.

Skip the embedded Node snapshot for the main process when the fuse is on
or the loaded v8 context snapshot is not the one this build shipped, and
bootstrap Node from scratch on the loaded blob as snapshot-less builds
do. The check is a size + V8-blob-header comparison against constants
that build/checksum_header.py now emits next to the existing SHA-256, so
it costs nothing at startup. Re-add the full verify-mksnapshot.py run to
one native test leg (linux x64).

(cherry picked from commit 11b7555)

…52877)

fix: let custom V8 snapshots reach the main process again (#52872)

Since the main process started booting from the embedded Node.js startup
snapshot (#51703), its context is deserialized from that blob, which was
built on top of the stock snapshot_blob.bin at build time. Objects a
custom snapshot puts into the default context -- electron-mksnapshot
users, and the browser_v8_context_snapshot.bin the
loadBrowserProcessSpecificV8Snapshot fuse selects -- therefore never
showed up in the main process on native builds (mac arm64, linux x64,
win x64), while cross-built targets, which ship without the Node
snapshot, kept working. spec/fixtures/snapshot-items-available ("f is
not defined") reproduces it, but CI only ran verify-mksnapshot.py with
--create-snapshot-only since the GHA migration.

Skip the embedded Node snapshot for the main process when the fuse is on
or the loaded v8 context snapshot is not the one this build shipped, and
bootstrap Node from scratch on the loaded blob as snapshot-less builds
do. The check is a size + V8-blob-header comparison against constants
that build/checksum_header.py now emits next to the existing SHA-256, so
it costs nothing at startup. Re-add the full verify-mksnapshot.py run to
one native test leg (linux x64).

(cherry picked from commit 11b7555)

…52878)

fix: let custom V8 snapshots reach the main process again (#52872)

Since the main process started booting from the embedded Node.js startup
snapshot (#51703), its context is deserialized from that blob, which was
built on top of the stock snapshot_blob.bin at build time. Objects a
custom snapshot puts into the default context -- electron-mksnapshot
users, and the browser_v8_context_snapshot.bin the
loadBrowserProcessSpecificV8Snapshot fuse selects -- therefore never
showed up in the main process on native builds (mac arm64, linux x64,
win x64), while cross-built targets, which ship without the Node
snapshot, kept working. spec/fixtures/snapshot-items-available ("f is
not defined") reproduces it, but CI only ran verify-mksnapshot.py with
--create-snapshot-only since the GHA migration.

Skip the embedded Node snapshot for the main process when the fuse is on
or the loaded v8 context snapshot is not the one this build shipped, and
bootstrap Node from scratch on the loaded blob as snapshot-less builds
do. The check is a size + V8-blob-header comparison against constants
that build/checksum_header.py now emits next to the existing SHA-256, so
it costs nothing at startup. Re-add the full verify-mksnapshot.py run to
one native test leg (linux x64).

(cherry picked from commit 11b7555)