94760 Add null return statements to nullable functions with implicit returns (a: text input, framework, f: material design, waiting for tree to go green)

94834 Add explicit null returns in flutter/test (a: text input, framework, f: material design, f: scrolling, f: cupertino, f: routes, waiting for tree to go green)

94898 Windows: Focus text field on gaining a11y focus (a: text input, framework, f: material design, f: cupertino, waiting for tree to go green)

94966 Delete and Backspace shortcuts accept optional Shift modifier (a: text input, framework, waiting for tree to go green)

95657 Migrate flutter_device_manager to null safety (a: text input, tool, waiting for tree to go green, a: null-safety, tech-debt)