[skia-sync] Merge upstream Skia main (tip)

[mattleibow]

Automated bleeding-edge sync from the tip of upstream Skia (google/skia main).

Companion skia PR: mono/skia#267

SkiaSharp side of Skia main tip sync (m150 tip, no version bump)

This PR is the parent-repo half of a bleeding-edge sync from google/skia main. The
companion mono/skia PR (head branch skia-sync/main) carries the actual upstream merge.

Because main is the in-development upstream tip rather than a chrome/m<N> milestone
branch, and CURRENT == TARGET == 150, this is NOT a version bump. The milestone,
soname, and NuGet versions are deliberately left alone. The only parent-repo changes are
cgmanifest.json (commit hash + upstream merge commit) and the externals/skia submodule
pointer.

Parent-repo changes

File	Change
externals/skia (submodule pointer)	b16789ec3540beaa43e8a71b050d9d328eb68025 → cd67ad79830bdf6fd7f09f2e5328cf85aa06b10d
cgmanifest.json mono/skia commitHash	→ cd67ad79830bdf6fd7f09f2e5328cf85aa06b10d
cgmanifest.json upstream_merge_commit	14d05ec761901b6e9e9193af8b347ab3a7f6fed0 → e793ca20f32abea8f96876d33c7ddabd3e5ed2d8

Untouched (intentionally — this is not a milestone bump):

• scripts/VERSIONS.txt (milestone, soname, NuGet versions)
• scripts/azure-templates-variables.yml (SKIASHARP_VERSION)
• cgmanifest.json chrome_milestone (stays at 150) and version (stays at chrome/m150)
• externals/skia/include/c/sk_types.h (SK_C_INCREMENT stays at 0)

Version files audit

libSkiaSharp     milestone    150     ← unchanged
libSkiaSharp     increment    0       ← unchanged (no new C API exports this sync)
SK_C_INCREMENT   0                    ← unchanged
SK_MILESTONE     150                  ← pinned in submodule (upstream had flipped to 151)
chrome_milestone 150                  ← unchanged
version          chrome/m150          ← unchanged

Binding changes

regenerate-bindings.ps1 ran cleanly. No SkiaApi.generated.cs diff — the C API surface
is byte-for-byte unchanged versus origin/main. (Header-rename churn upstream did not touch
any of the C API entry points; the only adjustment our shim needed was an
#include "include/private/SkTemplates.h" path fix in src/c/sk_font.cpp.)

HarfBuzz generated bindings were reverted as required (HarfBuzz updates are always separate
from Skia milestone updates).

C# wrapper changes

None. No new internal static P/Invoke declarations were generated, so there is nothing to
wrap. ABI surface unchanged.

Breaking change analysis

No breaking changes to the public SkiaSharp surface introduced by this sync.

Behavioural notes for downstream consumers:

• Upstream AtlasTextOp stride-mismatch handling was tightened from "log + early-return" to
  SkASSERTF_RELEASE. This is internal to the Ganesh text op path; SkiaSharp does not expose
  it directly, and the condition has historically not fired in tests, but a release-mode hit
  would now abort rather than silently skip. Recorded under "items needing human attention".
• LCD-on-SDF disabling: upstream's 95dbfa24e0 uses
  sk_ieee_float_divide(1.f, getMinScale()) where our pre-merge cherry-pick had
  getMaxScale(). Upstream's form is the authoritative one going forward; visible behaviour
  is equivalent on regular-scale draws and slightly different for extreme-anisotropic-scale
  draws. No SkiaSharp test regressions.

Build & test results (Linux x64)

Step	Result
dotnet tool restore	✅
dotnet cake --target=externals-linux --arch=x64 --gnArgs "skia_use_partition_alloc=false"	✅ libSkiaSharp.so + libHarfBuzzSharp.so
pwsh ./utils/generate.ps1 (via regenerate-bindings.ps1)	✅ no API diff
dotnet build binding/SkiaSharp/SkiaSharp.csproj	✅ 0 warnings, 0 errors
dotnet test tests/SkiaSharp.Tests.Console/SkiaSharp.Tests.Console.csproj	✅ Passed: 5569 / Skipped: 172 / Failed: 0 (`net10.0

Test output is preserved at /tmp/gh-aw/agent/test-output.txt (uploaded as workflow artifact).

Items needing human attention

1. Upstream is on milestone 151; SkiaSharp is still on 150. Upstream main's
   SkMilestone.h was flipped from 150 → 151 by chrome-branch-day (commit d30d2a1958).
   The companion mono/skia PR pins it back to 150 inside the submodule so the build's
   internal version check passes. A reviewer should decide whether the next sync should:
   • keep the pin (continuing to track tip without promoting our line); or
   • graduate SkiaSharp to m151 (would touch scripts/VERSIONS.txt, cgmanifest.json
chrome_milestone/version, soname, and ~30 NuGet version lines, plus drop the
     SkMilestone.h pin in mono/skia). The existing update-versions.ps1 script handles
     all of that automatically when invoked with -Current 150 -Target 151.
2. skia_use_partition_alloc=false is passed as a CLI gn arg, not baked into
   native/**/build.cake. This works (and complies with the workflow rule against
   modifying native build files) but is not durable — the next time someone runs
   dotnet cake --target=externals-linux without that flag, the build will fail because
   partition_alloc.gni is missing from our fork's DEPS. Recommend a follow-up to either
   (a) re-enable partition_alloc in externals/skia/DEPS, or (b) wire
   skia_use_partition_alloc=false into the platform build.cake files once the next
   real milestone bump rolls in.
3. All in-tree [M150] cherry-picks were upstreamed and dropped by the merge. This is
   the expected outcome of catching up to main, but it does mean any downstream consumers
   carrying additional patches on top of skiasharp should rebase carefully.

Other notes

• Native build environment was already provisioned (clang, libc++-dev/libc++abi-dev,
  fontconfig, ninja). No host packages were installed during the sync.
• externals-download was not used at any point during this sync. The shipped native
  binary comes from a fresh source build off the new merge.
• depot_tools' gclient_paths.py was touched by git-sync-deps (cache artifact); not
  committed.

Created by skia-upstream-sync.

[github-actions]

📦 Try the packages from this PR

Warning

Do not run these scripts without first reviewing the code in this PR.

Step 1 — Download the packages

bash / macOS / Linux:

curl -fsSL https://raw.githubusercontent.com/mono/SkiaSharp/main/scripts/get-skiasharp-pr.sh | bash -s -- 4255

PowerShell / Windows:

iex "& { $(irm https://raw.githubusercontent.com/mono/SkiaSharp/main/scripts/get-skiasharp-pr.ps1) } 4255"

Step 2 — Add the local NuGet source

dotnet nuget add source ~/.skiasharp/hives/pr-4255/packages --name skiasharp-pr-4255

More options

Option	Description
--successful-only / -SuccessfulOnly	Only use successful builds
--force / -Force	Overwrite previously downloaded packages
--list / -List	List available artifacts without downloading
--build-id ID / -BuildId ID	Download from a specific build

Or download manually from Azure Pipelines — look for the nuget artifact on the build for this PR.

Remove the source when you're done:

dotnet nuget remove source skiasharp-pr-4255

[mattleibow]

Closing stale skia-sync validation branch/PR to give the refactored auto-skia-sync workflow a clean slate for a fresh run.