[Packager] Source maps do not seem to work in Chrome

[jtremback]

Getting stacktraces like this:

Error: regeneratorRuntime is not defined
 stack: 
 callee$1$0 index.ios.bundle:1128
 componentDidMount index.ios.bundle:1130
 CallbackQueue.assign.notifyAll index.ios.bundle:4916
 ReactNativeReconcileTransaction.ON_DOM_READY_QUEUEING.close index.ios.bundle:14362
 ReactNativeReconcileTransaction.Mixin.closeAll index.ios.bundle:6220
 ReactNativeReconcileTransaction.Mixin.perform index.ios.bundle:6161
 batchedMountComponentIntoNode index.ios.bundle:15882
 Object.ReactDefaultBatchingStrategy.batchedUpdates index.ios.bundle:13951
 Object.batchedUpdates index.ios.bundle:4679
 Object.ReactNativeMount.renderComponent index.ios.bundle:15951
 Object.ReactPerf.measure.wrapper [as renderComponent] index.ios.bundle:5015
 Object.render index.ios.bundle:1310
 renderApplication index.ios.bundle:36269
 Object.AppRegistry.registerComponent.runnables.(anonymous index.ios.bundle:36171
 Object.AppRegistry.runApplication index.ios.bundle:36193
 jsCall index.ios.bundle:7335
 URL: undefined
 line: undefined
 message: regeneratorRuntime is not defined

However, the redbox on the phone is showing the right source files.