fix issue with end event not being emitted in executinStreaming

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[gbrail]

Sorry I didn't read this last month!

Would it be possible for you to use the little bit of test code that you wrote in the issue in "teststreaming.js"? That way we have a test case.

Also, I can't accept the PR until you sign the CLA -- sorry about that. If you can follow those instructions then we can do this.

Otherwise, if you can't then could you please respond and I'll just fix it since this is such a small change?

Thanks!