Summary:
Exporting ImageURISource because we needed to use it in a custom Image component. This should be a case for other people too since handling of `number` ImageSources and `ImageURISource` ImageSources are way different.
Release Notes:
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[GENERAL] [ENHANCEMENT] [Image] - Export "ImageURISource" Flow type
Pull Request resolved: https://github.com/facebook/react-native/pull/21305
Differential Revision: D10024160
Pulled By: rsnara
fbshipit-source-id: f074148345285217014b6ba6735cfdf3508563b5
783cb8e4a6