79805 Migrate vscode to null safety (a: null-safety, cla: yes, team, tool)

79806 Migrate android_workflow to null safety (a: null-safety, cla: yes, team, tool)

79807 Migrate some workflows and doctor validators to null safety (a: null-safety, cla: yes, team, tool)

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

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

79864 [flutter_tools] migrate cache to null safety (cla: yes, tool, waiting for tree to go green)