Summary:
This is the first step for adding my own async APIs for DevSupportManager to use in bridgeless mode.
To avoid having to add these APIs to the DevSupportManager interface + both of its implementations, I'm instead splitting DevSupportManager into a base class + final impl so I can more easily share logic with the new impl I'll create.
Changelog: [Internal]
Reviewed By: RSNara
Differential Revision: D19846619
fbshipit-source-id: c67b0231f4e6581fb484f9a4899ed0b7f08fb684
Emily Janzer
3f13c9abe6