68681 Apply Desktop specs for Tooltip (cla: yes, f: material design, framework, waiting for tree to go green)

68714 Revert “enable unnecessary_string_escapes and use_raw_strings” (a: internationalization, a: tests, cla: yes, f: cupertino, f: material design, framework, team, tool)

68723 [null-safety] try updating snippets for null safety (cla: yes, f: cupertino, f: material design, team)

68727 Fix floating behavior of long label and outline input border (cla: yes, f: material design, framework)

68736 Remove nullOk in MediaQuery.of (cla: yes, d: examples, f: cupertino, f: material design, framework, team)

68794 Add bottom to search bar (cla: yes, f: material design, framework, team)