Summary:
public
Attempting to load an undefined URL via XMLHttpRequest produced a confusing error deep within the network layer. This diff improves the networking stack to catch such errors earlier, and also adds a helpful error in the JS layer.
Fixes https://github.com/facebook/react-native/issues/4558
Reviewed By: javache
Differential Revision: D2811080
fb-gh-sync-id: 1837427e1080a0308f2c4f9a8a42bce2e041fb48
571e646543