Rewrite Taskcluster integration
This rewrites this repository’s integration with Taskcluster to have a decision task that runs an in-tree Python script to schedule a graph of other tasks with inter-dependencies, saved build artifacts, Docker images built from in-tree `Dockerfile`s, etc. This also adds support fail daily tasks, run automatically every 24 hours. See `etc/ci/taskcluster/README.md` for more details.
Example of a green build with web-platform-tests enabled: https://tools.taskcluster.net/groups/aDL0pUBkSmuhezT1OF80_g
For now this PR only enables one task, equivalent to Buildbot’s `linux-dev` job. (Running Tidy and other linting tools, compiling in debug mode, and running unit tests.) At this time Homu does **not** yet block PRs from merging on a successful result from Taskcluster, but I plan to do this soon after this PR lands.
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jni-rs update
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Get the right pixel density on Android
Fix#21605 and fix#21504
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Use standard buffer format for DEPTH_STENCIL
This makes the Going Home title display for me on my Pixel 2.
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Partially revert #21746.
This reverts the relevant bits from #21746 so that style and dependencies can
build with stable.
This is important because:
* `selectors` is a published crate.
* Gecko compiles with stable (more or less).
I reviewed that PR under the assumption that the union feature was stable, since
untagged unions are stable since 1.19, but turns out that smallvec uses non-Copy
types in unions, which are still unstable.
This leaves the union feature used on Servo, so that it gets testing, taking
advantage of features being additive.
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This reverts the relevant bits from #21746 so that style and dependencies can
build with stable.
This is important because:
* `selectors` is a published crate.
* Gecko compiles with stable (more or less).
I reviewed that PR under the assumption that the union feature was stable, since
untagged unions are stable since 1.19, but turns out that smallvec uses non-Copy
types in unions, which are still unstable.
This leaves the union feature used on Servo, so that it gets testing, taking
advantage of features being additive.
The behavior the WG proposed is way more subtle than what that bug implements,
including:
* Implementing two logical overflow longhands.
* Expanding the overflow shorthand to different longhands depending on the
syntax of that.
Meanwhile, Blink hasn't done the swap and will ship the same behavior that we
shipped in Firefox 61 (bug 1453148), that is, overflow-x, then overflow-y.
So I think lacking a clear way forward we should revert this change and preserve
our shipped behavior.
Differential Revision: https://phabricator.services.mozilla.com/D6317
