Summary:
Adds a queue to postMessage so that messages sent close together are not lost.
Setting location="a";location="b" results in only "b" reaching shouldStartLoadWithRequest. Making the second update asynchronous with setTimeout does not fix the issue unless a delay is added.
With this update, postMessage queues "b" until it gets a "message:received" event that confirms "a" has already been processed.
The included test sends two messages from a webview and checks that both are received. It fails against the preexisting code with the first message being dropped.
Closes https://github.com/facebook/react-native/pull/11304
Differential Revision: D5481385
Pulled By: hramos
fbshipit-source-id: 9b6af195eeff8f20c820e2fcdac997c90763e840
42f7b9e717
