Check that the marked bit of an object is set if assigned during a
prefinalizer to a Member in a live object or a Persistent.

Bug: v8:11749
Change-Id: I993c0d226a4157698591e1f7bc0c55e5c79239b6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2897093
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74672}

The marking verifier already traverses the whole heap using page
iteration. Add an option to allow checking that the verifier pass
finds the same amount of live bytes as the marker traversal.

Bug: chromium:1056170
Change-Id: I1dc4cd0c04147b8cd3e3eb7678276b665336e615
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2902724
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74630}

Bug: v8:10724
Change-Id: Ia0b6d6d25e6b9d7b44b4dfa94705e9cd5103cc8e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2316303Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69094}

The parser is capable of processing full GN grammar. The generator uses
the visitor and the builder patterns. The visitor handles call expressions
(e.g. target declarations), GN expressions (e.g. is_clang && !is_win),
conditional and assignment statements. Builder is used to generate a
particular output. For example, this CL brings in CMakeBuilder for cmake
generation, but same infrastructure can be reused for generation of
amalgamated sources.

Things that are not yet automatically generated:
1) Automatic generation of config variables (from declare_args).
2) Dependency scanning. Since we only have limited number of targets,
   this is not a big issue at the moment.

Followup CLs will include:
- test targets;
- sample targets.

Bug: v8:10724
Change-Id: I0b31910aca67f0e02ab142b2d35f4338345e7f29
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2306790
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69017}