Julia Lavrova

This commit introduces a **new capability** within the **`skparagraph`** module to precisely control letter spacing, especially for script languages. A new boolean property, `fLetterSpacingByCSSSpec`, is added to `ParagraphStyle` to enable conditional application of letter spacing within `applySpacingAndBuildClusterTable` based on CSS specifications and script characteristics. This enhancement aims to **unblock customers** by providing more accurate text rendering for complex scripts like Arabic, as verified by new test cases, while carefully avoiding regressions for existing integrations like Flutter.

This commit **refines letter spacing application** within the **`skparagraph` module**, specifically for **script languages**, by ensuring that spacing is applied only to **whitespaces**. It introduces `addAllLetterSpacesEvenly` to manage letter spacing for entire text runs and modifies `addLetterSpacesEvenly` to be whitespace-aware, preventing incorrect spacing of non-whitespace characters in languages like Arabic. Additionally, an incorrect trimming operation in `trimEndSpaces` that caused issues with **RTL text** is disabled. This **fix** significantly improves the **visual fidelity** and **correctness** of text layout for internationalized content, particularly for complex scripts.

This commit **relands** the essential changes required to enable **Fuchsia** to utilize the **Fontations** font rendering library. It **refactors** the `SkFontMgr_fuchsia` implementation, introducing a new `SkFontMgr_New_Fuchsia` overload that accepts a `unique_ptr<SkFontScanner>` and leverages a generic `SkTypeface_proxy`. This **feature enablement** was previously reverted due to a Flutter build issue, which has now been resolved, allowing the integration to proceed. The change primarily affects the **Fuchsia font manager** and its typeface creation mechanisms, with minor debugging prints added to assist in monitoring the integration.

This commit **fixes a rendering bug** in the **`skparagraph` module** by **preventing letter spacing from being applied to script languages**, particularly cursive scripts. It **refactors the letter spacing logic** within `Run.cpp` and `Run.h` by renaming functions to `addLetterSpacesEvenly` and introducing an `isCursiveScript` check. `ParagraphImpl.cpp` and `TextLine.cpp` are updated to utilize this new logic, ensuring that text layout correctly **ignores letter spacing for languages where it's inappropriate**. A new test in `SkParagraphTest.cpp` validates this improved behavior for Arabic and English text, enhancing the **correctness of text rendering for internationalized content**.

This commit introduces a **new capability** within the **Fuchsia font management system**, specifically enabling it to integrate with **Fontations** by allowing custom font scanning. It **refactors** the `SkFontMgr_fuchsia` implementation to accept and utilize a custom `SkFontScanner`, adding a new overload for `SkFontMgr_New_Fuchsia` in the public API. This change is crucial for the **Fuchsia port** to leverage modern font rendering, providing the necessary infrastructure for external font processing. Additionally, typeface creation within the manager is updated to use `SkTypeface_proxy` for improved handling.

This commit **reverts** a previous change that modified the **internal font cache** within the **`skparagraph`** module to operate on a per-name/face basis. It undoes alterations to the `FontCollection` header and implementation, specifically restoring the original `FamilyKey` struct, `findTypeface` methods, and the `fTypefaces` cache type. This **maintenance revert** addresses a "breaking" issue introduced by the original change, restoring the module's font collection and caching logic to its prior, stable state. Consequently, the intended flexibility for callers to pass font names in any order while benefiting from the cache is no longer active.

This commit **reverts** a recent **feature addition** to the **SkParagraph module** due to a **build break**. It specifically removes the `kExcludeTrailingSpaces` option from the `RectWidthStyle` enum and the associated logic within the `getRectsForRange` method in `TextLine.cpp`. Consequently, the `getRectsForRange` function will no longer offer the capability to compute text bounding boxes that exclude trailing whitespace. This restores the previous behavior where all calculated rectangles for a text range include any trailing spaces, impacting precise text decoration use cases that relied on tighter glyph-only bounding boxes.

This commit performs a **maintenance update** for the `abseil-cpp` dependency, specifically addressing a build issue where the previous version was missing a file in the **GN build** that impacted **Dawn**. The update involves changing the commit hash in the main `DEPS` file and `bazel/deps.json`, alongside updating the version string in `infra/bots/deps/deps_gen.go`. This ensures the project can correctly utilize the latest `abseil-cpp` version, resolving build failures and maintaining compatibility, especially for the **Dawn** graphics API.

This commit **fixes a build issue** that was preventing a Chrome roll by **removing the `[[deprecated]]` attribute** from the `getPath` function declaration. Specifically, this **maintenance refactoring** targets the `SkFont::getPath` method within the **Skia core library**'s `include/core/SkFont.h` header. The attribute was causing compilation failures in stricter build environments, which treated `[[deprecated]]` as an error. By eliminating this problematic attribute, the change **unblocks downstream Chrome builds** and ensures smoother integration.

This commit provides a **bug fix** and **robustness improvement** for the **SkUnicode Bidi text reordering logic**. It introduces **null pointer assertions** and **early return conditions** within the `reorderVisual` and `bidi_reorderVisual` methods across various `SkUnicode` implementations. This ensures that the Bidi reordering functions gracefully handle cases with empty level counts or null run levels, preventing potential crashes or incorrect visual ordering. The change affects the **SkUnicode module's** Bidi implementations, including ICU, ICU4X, and client-side versions, enhancing the stability of text layout.

This commit introduces a **small fix and enhancement** to the **CanvasKit Unicode CodeUnits API**, specifically within the **BiDi (Bidirectional Text) module**. It **adds a new helper function `Int16ArrayToCodeUnitsFlags`** in `modules/canvaskit/bidi.js` to correctly transform the output of `_compute` and modifies `getBidiRegions` to utilize it. Additionally, it **refactors** the internal C++ helper `getClientUnicode` to `getBidiUnicode` in `modules/canvaskit/bidi_bindings.cpp` for clarity. The commit also includes **fixes** to the example `bidi.html` and `bidi_test.js` to ensure they correctly access the 'flags' property from the `CanvasKit.CodeUnits.compute` API's output, improving the robustness and correctness of the **BiDi text processing**.

This commit performs **maintenance** and **refactoring** on the **CanvasKit Bidi API** to enhance its usability. The `getBidiRegions` function in `modules/canvaskit/bidi.js` now returns an array of objects, each containing an `index` property, rather than a raw `Int32Array`. This semantic change, facilitated by the new `Int32ArrayToBidiIndexes` helper, requires consumers of the Bidi API to update their code to access the `index` property. **Example usage** in `modules/canvaskit/npm_build/bidi.html` and **Bidi behavior tests** in `modules/canvaskit/tests/bidi_test.js` have been updated accordingly.

This commit delivers **fixes and refactoring** to improve the **Bidirectional (Bidi) text API** within **CanvasKit** and its underlying **SkUnicode** module. It refines the `forEachBidiRegion` template function in `SkUnicode.h` and the `makeBidiIterator` implementation to ensure accurate calculation and reporting of Bidi region boundaries and levels. The `_getBidiRegions` logic in `modules/canvaskit/bidi_bindings.cpp` is updated to leverage these improvements, correctly handling UTF-16 strings. These changes enhance the reliability and consistency of **Bidirectional text rendering** for CanvasKit users, with an accompanying test in `bidi_test.js` to verify UTF-16 based region ends.

This commit introduces comprehensive **Bidirectional (Bidi) text support** to the **CanvasKit** module, enabling proper rendering and manipulation of text containing mixed left-to-right and right-to-left scripts. This **new capability** exposes JavaScript APIs like `getBidiRegions`, `reorderVisuals`, and `CodeUnitFlags` for analyzing text directionality and reordering visual display, backed by a new Bidi-specific implementation within the **SkUnicode** module. The work involved significant **API development**, **Emscripten bindings**, and extensive **build system updates** (GN, Bazel, Makefiles) to conditionally integrate this functionality. This feature provides crucial support for **right-to-left (RTL) languages** and complex text layouts, complete with new unit tests and an example page.

This commit **adds a new example slide** to the **`skparagraph` module**'s demonstration suite. It introduces the `ParagraphHangingWhitespaces` slide within `modules/skparagraph/slides/ParagraphSlide.cpp` to visually illustrate how `SkParagraph` renders and handles **hanging whitespaces** in text layouts. This **feature demonstration** enhances the project's examples, providing a clear visual reference for developers on this specific text rendering behavior. The new slide helps to document and test the correct drawing of these particular whitespace scenarios.

This commit **fixes a bug** in the **CanvasKit** binding for `SkParagraph::getShapedLines`, ensuring it correctly returns the associated **`SkTypeface` object** instead of null. Previously, this method might have returned an incorrect or null typeface, hindering proper font introspection. To facilitate verification and provide more utility, a new `getFamilyName` method was added to the `SkTypeface` bindings, allowing retrieval of the font family name. This **enhances the `SkParagraph` API** in CanvasKit, providing accurate typeface information, and is validated by new tests and an example page.