79804 Migrate linux_doctor to null safety (a: null-safety, cla: yes, team, tool)

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)

79888 [web] Fix url strategy null safety (a: null-safety, cla: yes, f: routes, platform-web, waiting for tree to go green)