This decouples the Impeller on-by-default effort from the release schedule and [plugin migrations](flutter/flutter#151018).

The plugin migration documented in [go/impeller-plugin-migration][plugin-migration] is still recommended and facilitates zero-copy texture transfers between OpenGL and Vulkan. To recap, the plugin migration is to move away from the OpenGL-only SurfaceTexture APIs in the plugin interface.

This patch facilitates rendering OpenGL textures in a Vulkan renderer using texture trampolining using a single device-device transfer on all devices that support Impeller using the Vulkan renderer.

The performance of this approach is more than acceptable but at the cost of an additional texture allocation and will serve as a fallback to the for any remaining unmigrated plugins (all first-party plugins will already be migrated when the Impeller is on by default and we are following up on the migration of the major third-party plugins as well).

This is a straight improvement to the current state of things were unmigrated plugins will render an empty quad.

Follow up to #54018.

Workaround for flutter/flutter#152099

…54032)

New flags on SaveLayerOptions will report if a saveLayer result is unbounded because a rendering operation within its contents did not have a definable bounds and there was no clip installed at the time (consider DrawPaint for example). A similar flag is found on DisplayList objects which reports if their top level had an unbounded operation.

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2024-07-23 [email protected] Update Skia milestone to 129
2024-07-23 [email protected] Use a separate overload for stable-ID calculation.
2024-07-23 [email protected] Migrate the specialized function-decl key into SkSLSpecialization.

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Refactors flip backdrop into a shared method and adds supported for emulated advanced blends in exp canvas. Last missing feature (AFAIK).

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2024-07-23 [email protected] Don't test F16 draws with advanced blend modes
2024-07-23 [email protected] Android SkFontMgr prioritize stated weight
2024-07-23 [email protected] Merge 4 release notes into RELEASE_NOTES.md
2024-07-23 [email protected] Roll vulkan-deps from 5d0bdd3702f7 to f211552c7990 (2 revisions)

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2024-07-23 [email protected] Version 3.6.0-74.0.dev

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2024-07-23 [email protected] Disable path_text_clipped_uncached on Pixel4XL Vulkan configs
2024-07-23 [email protected] Mark samplers as explicitly-sampled when passing them to a function.
2024-07-23 [email protected] Revert "[skif] Use src blending when possible"
2024-07-23 [email protected] Further limit F16 draw test
2024-07-23 [email protected] Remove use of enable_skslc flag
2024-07-23 [email protected] Simplify control flow in css_hwb_to_srgb.
2024-07-23 [email protected] [loong64] Optimize gauss blur imagefilter.
2024-07-23 [email protected] [SkSL] Change specialization mapping to expression
2024-07-23 [email protected] [graphite] Fix basic drawShadow functionality.

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2024-07-23 [email protected] [graphite] Use non-aa bounds renderer for pixel-aligned rects

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Since this method isn't mutating the pool, we should mark it const.

Cleanup spotted while working on #54056.

No test because no semantic change. The compiler is the test.

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`FlutterPlatformViewLayerPool` is a pool of iOS layers used for rendering platform views on iOS. When layers are no longer needed, we currently mark them available for re-use but we never actually flush them and thus recover the memory associated with these layers once we know that the layers are no longer needed.

We now flush the layer pool on `SubmitFrame` if a previously-used layer is no longer used in the current frame. In theory, this could cause a performance regression in the case where an additional layer is needed every second or third frame, but we should keep it simple on the first pass and only complicate things later if warranted.

Fixes: flutter/flutter#152053

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…cOe... (#54063)

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…54065)

Fixes 2 problems recently uncovered in the DisplayList verbose comparison test mechanism:

- The verbose compare methods never asserted a test failure, relying on the caller to do so from their return value - but they also did not prompt the caller to check the return value. So a `[[nodiscard]]` is added to remind test writers that they need to assert on the return value
- As a result of the above, some bad tests were recently added to the tree that were failing but did not assert a test failure. Now that the `[[nodiscard]]` is added, they failed to compile and had to have asserts added.

A secondary problem is that those non-failing tests were inadvertently cherry-picked from a reverted PR that is being reintroduced in incremental sections so as to avoid large scale golden image failures. The tests depend on parts of that PR that haven't been pulled forward yet (but will soon be) so those tests shouldn't have been added in the first place (and were failing, but not causing a gtest failure because of their missing asserts). They remain here, but their results are reversed to indicate the current state of affairs (they assert that the missing functionality isn't in place yet). Their assertions will be reverted when/as the missing functionality is pulled forward in a more incremental (responsible) way.

…... (#54064)

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2024-07-23 [email protected] Version 3.6.0-75.0.dev

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This is in preparation for
https://dart-review.googlesource.com/c/sdk/+/373884, which will add length to the extension type itself. This will shadow the extension member, so we should make sure the type signatures match.