Summary:
It is quite confusing that the 'data:' uri scheme is not documented, but working.
It is very useful when getting e.g. an icon from a REST call.
Also, the mandatory size style for network & data images should be mentioned here, not only in the image guide.
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Closes https://github.com/facebook/react-native/pull/14826
Differential Revision: D5401671
Pulled By: hramos
fbshipit-source-id: 8f1f28a94095eeaccae9234e059e0983ba3556b2
ec8118b637