net/http: update bundles http2
Updates http2 to x/net/http2 git rev
906cda9 for:
http2: add configurable knobs for the server's receive window
https://golang.org/cl/37226
http2/hpack: speedup Encoder.searchTable
https://golang.org/cl/37406
http2: Add opt-in option to Framer to allow DataFrame struct reuse
https://golang.org/cl/34812
http2: replace fixedBuffer with dataBuffer
https://golang.org/cl/37400
http2/hpack: remove hpack's constant time string comparison
https://golang.org/cl/37394
Updates golang/go#16512
Updates golang/go#18404
Change-Id: I1ad7c95c404ead4ced7f85af061cf811b299a288
Reviewed-on: https://go-review.googlesource.com/37500
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>