fix(web_ui): move prepareToDraw after raster to improve concurrency and stability#183791
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…nd stability Moving prepareToDraw after the synchronous raster recording phase ensures that the UI state is captured immediately. This prevents potential race conditions in Skwasm where resizing the surface immediately before measuring and painting could lead to uninitialized Skia resources or incorrect rendering states. By deferring physical surface sizing until after the pictures are recorded, we also allow asynchronous surface preparation to better overlap with other work, improving overall frame performance. Fixes flutter#182354
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This pull request refactors the drawing logic in ViewRasterizer by moving the prepareToDraw call to after the compositorFrame.raster call. This change is aimed at improving concurrency and stability. The PR includes two new test files to validate the change: rasterizer_order_test.dart verifies the correct sequence of operations during rasterization, and rasterizer_resize_golden_test.dart adds a golden test to ensure rendering is correct after resizing the view.
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flutter/flutter@d117642...dd64978 2026-03-18 [email protected] Roll Skia from 2fb5fa71eb12 to f0a13e5efbad (2 revisions) (flutter/flutter#183830) 2026-03-18 [email protected] Roll Skia from ae3d36cb9e29 to 2fb5fa71eb12 (3 revisions) (flutter/flutter#183823) 2026-03-18 [email protected] Linux reuse sibling (flutter/flutter#183653) 2026-03-18 [email protected] Roll Skia from 84a180a1fa80 to ae3d36cb9e29 (4 revisions) (flutter/flutter#183812) 2026-03-18 [email protected] fix(web): handle asynchronously disposed platform views (flutter/flutter#183666) 2026-03-17 [email protected] (Test cross-imports) Remove legacy Material import from sliver_constraints_test (flutter/flutter#183351) 2026-03-17 [email protected] Fix Android Studio pluginsPath when version is unknown (do not use 0.0) (flutter/flutter#182681) 2026-03-17 [email protected] Fixes animation glitch into bottom sheet (flutter/flutter#183303) 2026-03-17 [email protected] Handle#6537 second grouped test (flutter/flutter#182529) 2026-03-17 [email protected] Add a Clarification for the docs of suggestionsBuilder of SearchAnchor (flutter/flutter#183106) 2026-03-17 [email protected] Remove obsolete null checks from style guide (flutter/flutter#181703) 2026-03-17 [email protected] [Impeller] Do not delete the GL object in a HandleGLES if the handle has a cleanup callback (flutter/flutter#183561) 2026-03-17 [email protected] Encode source file patches as UTF-8 in the code formatter script (flutter/flutter#183761) 2026-03-17 [email protected] Fix widget inspector control layout and add safe area regression test (flutter/flutter#180789) 2026-03-17 [email protected] Reland "[Android] Add mechanism for setting Android engine flags via Android manifest (take 2)" (flutter/flutter#182522) 2026-03-17 [email protected] fix(web): fix crash in Skwasm when transferring non-transferable texture sources (flutter/flutter#183799) 2026-03-17 [email protected] Roll Skia from dba893a44d7a to 84a180a1fa80 (7 revisions) (flutter/flutter#183803) 2026-03-17 [email protected] Framework: Improve DropdownButton selectedItemBuilder assertion (flutter/flutter#183732) 2026-03-17 [email protected] Add mainAxisAlignment to NavigationRail (flutter/flutter#183514) 2026-03-17 [email protected] Update android triage process to not look at unassigned p1s every week (flutter/flutter#183805) 2026-03-17 [email protected] Adds macos impeller new gallery transition perf test. (flutter/flutter#183802) 2026-03-17 [email protected] fix(web_ui): move prepareToDraw after raster to improve concurrency and stability (flutter/flutter#183791) 2026-03-17 [email protected] [build] Generate debug info for assembly. (flutter/flutter#183425) 2026-03-17 [email protected] [web] Fix occasional failure to find Chrome tab (flutter/flutter#183737) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md
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Moving prepareToDraw after the synchronous raster recording phase ensures that the UI state is captured immediately. This prevents potential race conditions in Skwasm where resizing the surface immediately before measuring and painting could lead to uninitialized Skia resources or incorrect rendering states.
By deferring physical surface sizing until after the pictures are recorded, we also allow asynchronous surface preparation to better overlap with other work, improving overall frame performance.
Fixes #182354
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