Chrome Version: 57.0.2987.133 (Official Build) (64-bit)
OS: mac os x

What steps will reproduce the problem?
(1) Visit https://http2-push.appspot.com/. Open up the network panel
(2) The main page uses Link rel=preload to h2 push resources: app.css, elements.html. See headers screenshot
(3) DevTools reports the Initiator of these resources as "Other"

What is the expected result?

Initiator should be "Push".

What happens instead?

Disabling QUIC in about:flags confirms that DevTools is showing "Push" when the protocol is h2.

net-internals confirms the resource(s) are being pushed:

t= 5118 [st=  563]  QUIC_SESSION_PUSH_PROMISE_RECEIVED
--> :method: GET
    :scheme: https
    :authority: http2-push.appspot.com
    :path: /bower_components/iron-selector/iron-selectable.html
    pragma: no-cache
    cache-control: no-cache
    upgrade-insecure-requests: 1
    user-agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.133 Safari/537.36
    accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
    accept-encoding: gzip, deflate, sdch, br
    accept-language: en-US,en;q=0.8
    x-cloud-trace-context: e58db14c65f5344a1577e52cfdf937f7/3993859914463054422
    cookie: [39 bytes were stripped]
    referer: https://http2-push.appspot.com/
--> id = 73
--> promised_stream_id = 162

Developer are getting confused because App Engine (depending on the env), now serves resources over h2 and quic. It's become hard to verify that an app is actually pushing resources without diving into chrome:net-internals. Many devs don't know about that page.

Marking this as a P1 because it's been an issue for a while.