14046 fix try to copy null will cause crash on iOS (cla: yes)

14053 Revert “Do not default to downstream affinity on iOS insertText” (cla: yes)

14054 Roll src/third_party/skia 40a7dfc268b6..861ac61cb1a9 (34 commits) (autoroller: commit, cla: yes)

14056 A11y desktop fix the method call (accessibility, cla: yes, platform-web)

14058 Roll src/third_party/dart 134e0e28cd..96e7a4ff30 (38 commits) (cla: yes)