Part of #39418. See that PR for a full description.
Moves:
- `read_json_from_file`
- `write_json_to_file`
- `IpcSendResult`
- `IpcSend`
Renames:
- `CoreResourceThreadPool` to `ThreadPool` (shorter and more
descriptive, as we use it for more than the core resource thread now)
Signed-off-by: Ashwin Naren <arihant2math@gmail.com>
