Summary:
Currently on iOS and Android focus/blur events trigger onPressIn/onPressOut. Based on discussions with people are several companies who use react-native we're proposing instead triggering new events onFocus/onBlur. Initial discussion on Slack with some from the core team on Slack seemed positive.
Couple reasons:
* The current API behavior overloads onPressIn/onPressOut. That means on platforms like react-native-web, if focus/blur support was added (as we're hoping for), even though onPressIn/onPressOut would be useful as the name describes, you wouldn't be able to distinguish between it and browser element focus/blur events.
* The names aren't as self-documenting/intuitive as onFocus/onBlur, especially for react-dom users.
There aren't any current tests around this, but I intend to add them if we solidify the API.
There's also an option question on the transition--do we deprecate the existing API with a warning? This PR just deprecates them, though it will on any TV platform when something becomes focused regardless of whether they use the API or not. This isn't ideal. It's not clear if there are alternatives or if just right away breaking the API for TV users is the correct solution, if we can get consensus between the few parties who are using it.
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I'm interested to hear counter points or prior discussions.
Cc/ matthargett dlowder-salesforce rozele
Closes https://github.com/facebook/react-native/pull/18470
Differential Revision: D8368109
Pulled By: hramos
fbshipit-source-id: 22587b82e091645e748b6c2d721fdff06d54837f
baa61ddc9c