77098 Clean-up analysis_options files (a: internationalization, a: tests, cla: yes, d: examples, framework, team, waiting for tree to go green)

77099 Turn on sized_box_for_whitespace lint, fix instances and tests. (a: accessibility, a: tests, cla: yes, d: examples, f: cupertino, f: material design, framework, team, waiting for tree to go green)

77107 Improve error messaging and documentation for Scrollbar.isAlwaysShown (a: error message, cla: yes, d: api docs, d: examples, documentation, f: scrolling, framework, waiting for tree to go green)

77118 Align more closely with package:test (a: accessibility, a: tests, cla: yes, d: examples, f: material design, framework, team, tool, waiting for tree to go green)