Chris Yang 5c12a78db9 [ios] making objective-C smart pointers support ARC (flutter/engine#47612) ...

Moving the implementation from https://codereview.chromium.org/1855483004 into the code base, including:

- scoped_nsobject, scoped_nsprotocol, scoped_block will support both mrc and arc
- Added parent class scoped_typeref for shared code between scoped_block and scoped_nsobject
- moving OwnershipPolicy to its own file

The implementation of the smart pointers are almost identical to https://codereview.chromium.org/1855483004 besides some syntax preference differences between chromium and flutter.

This PR also migrated [VsyncWaiterIosTest.mm](https://github.com/flutter/engine/pull/47612/files#diff-c98ce1a2aca65c29bbc444523b66921a53ecce5ff39a420b4eda7dbfe8ca1cc7) to ARC with scoped_nsobject

fixes https://github.com/flutter/flutter/issues/137802

[C++, Objective-C, Java style guides]: https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style

2023-11-07 19:25:45 +00:00

..

src/flutter

[ios] making objective-C smart pointers support ARC (flutter/engine#47612)

2023-11-07 19:25:45 +00:00