<!-- Please describe your changes on the following line: -->
Migrated the trace-layout code from old `rustc-serialize` to `serde_json`. This will help us iterate faster on the layout viewer (#13432), #13436, #12675 and fix#12936.
---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#12936 (github issue number if applicable).
<!-- Either: -->
- [ ] There are tests for these changes OR
- [x] These changes do not require tests because it's a relatively low risk debug tool
<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->
Source-Repo: https://github.com/servo/servo
Source-Revision: 1c26f44cbb23e7da3b9d63f0223c8d5d43eec958
This creates a sharp distinction between `Arc<Flow>`s, which may be
owned by anyone, and `FlowRef`s, which may only be owned by the
traversal code. By checking the reference count, we ensure that a `Flow`
cannot be pointed to by `Arc`s and `FlowRef`s simultaneously.
This is not a complete fix for #6503, though it is a necessary start
(enforcing the no-aliasing rule of `FlowRef::deref_mut` will require far
more work).
---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#14014 (github issue number if applicable).
- [X] These changes do not require tests because the existing tests, plus the added assertions, should be sufficient
Source-Repo: https://github.com/servo/servo
Source-Revision: 2b4a7b0b7ad9dd568dfde15ab47dc634ec561d70
This also fixes Undefined Behavior in build_display_list_for_subtree.
Source-Repo: https://github.com/servo/servo
Source-Revision: a316fb73e5fb1b086516ba6786c5ae4c302c3c62
By definition of a weak pointer, these implementations cannot be safe.
Source-Repo: https://github.com/servo/servo
Source-Revision: 82be491fa318f742720dc0a31f6c1b24beb57a3d
Cycles were being created in the flow tree since absolutely positioned
descendants had pointers to their containing blocks. This adds
WeakFlowRef (based on Weak<T>) and makes these backpointers weak
references. This also harmonizes our custom Arc<T>, FlowRef, to be
consistent with the upstream implementation.
Fixes#4915.
Source-Repo: https://github.com/servo/servo
Source-Revision: f5ddbcf19fcd477dee61d6c03434ef7cfca188bf
This patch switches FlowRefs to using the Deref and DerefMut traits, instead of
the custom `get` and `get_mut` functions.
Source-Repo: https://github.com/servo/servo
Source-Revision: 6a11ee89de82abae9d6607a6c2890692df5259eb
