67176 Add benchmark/test for drawing images across frames (cla: yes, severe: performance, team, waiting for tree to go green)

67177 Reland dispose images when done (#67100) (a: tests, cla: yes, framework)

67183 Revert “migrate some material files to nullsafety” (cla: yes, f: material design, framework)

67193 Roll flutter engine to a24c7c13925e4e3282f7b85814b70e63782fa057 (cla: yes, engine, framework)

67197 Preserve composing range if possible on sel change (a: desktop, a: text input, cla: yes, framework)

67218 change the documentation of bottom navigation bar (cla: yes, framework, waiting for tree to go green)