Summary:
Support `xhr.send(data)` for typed arrays.
**Test plan:** run UIExplorer example on iOS and Android.
Closes https://github.com/facebook/react-native/pull/11904
Differential Revision: D4425551
fbshipit-source-id: 065ab5873407a406ca4a831068ab138606c3361b
Summary:
The XHRExample file had been forked between iOS and Android for various reasons that are no longer valid, making maintenance unnecessarily difficult. New features demos had in fact been added in separate files to avoid further duplication. This change continues on that same trajectory and splits the entire example file into multiple files. This makes them much easier to handle. We also get rid of the iOS/Android fork.
**Test plan:** Run UIExplorer app, specifically the XHR examples, on both iOS and Android.
Closes https://github.com/facebook/react-native/pull/11901
Differential Revision: D4419882
Pulled By: ericvicenti
fbshipit-source-id: ec12836dfa8e1b9259b92a7510914857a8db58d5
