Summary:Add a couple functions to show and hide a small window with buttons to start/stop
systrace and reload the current bridge. After stop profiling, the results will
be saved to a temporary file, and a share sheet will show up with the file attached
so that you can send it to your computer whatever way is more convenient.
Depends on D2700069
Reviewed By: jspahrsummers
Differential Revision: D2811560
fb-gh-sync-id: 5e91ece3a7ea748d4cb5fbc612a9b76ab80fc8f3
shipit-source-id: 5e91ece3a7ea748d4cb5fbc612a9b76ab80fc8f3