20644 fix build (cla: yes)

20647 fuchsia: Convert legacy permutations to build flag (affects: engine, affects: tests, cla: yes, code health, platform-fuchsia)

20651 Use references for C++ MethodResult and EventSink (cla: yes)

20660 send newline char when input type is multiline (cla: yes, waiting for tree to go green)

20662 [windows] Mostly eliminate the state structs (affects: desktop, cla: yes, platform-windows)

20665 All shape related structs are together (cla: yes, waiting for tree to go green)

20668 [windows] Add horizontal scroll support (affects: desktop, cla: yes, platform-windows)