26996 Add SPIR-V FragmentShader API to painting.dart (platform-android, cla: yes, platform-web, platform-fuchsia)

27413 Bump Android version and add more info to create_sdk_cipd_package.sh (cla: yes, waiting for tree to go green)

27423 fuchsia: Add scaffolding and basic implementation for flatland migration (cla: yes, platform-fuchsia)

27472 Remove dead localization code from the iOS embedder (platform-ios, cla: yes, waiting for tree to go green, tech-debt)

27662 Implementation of two or more threads merging for multiple platform views (platform-android, cla: yes)

27687 Fix a typo in https://github.com/flutter/engine/pull/27311 (cla: yes, waiting for tree to go green, platform-windows, needs tests)