Summary:
Renames `EventSubscription.js`, `EmitterSubscription.js`, and `EventSubscriptionVendor.js` to `_EventSubscription.js`, `_EmitterSubscription.js`, and `_EventSubscriptionVendor.js`, respectively.
This is to indicate that those files are implementation details and should not be directly referenced. Instead, the `EventSubscription` type exported from `EventEmitter.js` should be used.
The remaining stragglers that are importing `_EmitterSubscription.js` and `_EventSubscriptionVendor.js` after this commit will be cleaned up when `RCTDeviceEventEmitter` is refactored.
Changelog:
[Internal]
(Note: this ignores all push blocking failures!)
Reviewed By: cpojer
Differential Revision: D22182310
fbshipit-source-id: 82be685f231395bd7b8e9986141b5df1367bec71
