Add headers prop in source array type prop

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Closes #16155

Differential Revision: D5962399

Pulled By: shergin

fbshipit-source-id: b7a44d53d875b32d04c1b876eb7ec2f30a9d0d80

Libraries/Image/Image.android.js

@@ -107,6 +107,7 @@ var Image = createReactClass({
           uri: PropTypes.string,
           width: PropTypes.number,
           height: PropTypes.number,
+          headers: PropTypes.objectOf(PropTypes.string),
         }))
     ]),
     /**