79813 Migrate intellij_validator to null safety (a: null-safety, cla: yes, team, tool)

79816 Fix an NNBD error in the Gallery text form field demo (cla: yes, f: material design, team, waiting for tree to go green)

79817 [web] Enable Cupertino text field tests on web (a: tests, a: text input, cla: yes, f: cupertino, framework, platform-web, tech-debt, waiting for tree to go green)

79827 [flutter_tools] generate empty plugin registrants for winuwp and fix local engine for winuwp_ (cla: yes, tool)

79828 Revert “Fix error when choose noon on time picker (#78478)” (cla: yes, f: material design, framework)