http2: mostly test for Transport memory issue
http2: mostly test for Transport memory issue

Updates golang/go#20448

Change-Id: I6366b0b0b36d81095ab347ca35e1e72169c05c15
Reviewed-on: https://go-review.googlesource.com/43853
Run-TryBot: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Tom Bergan <3b77d7da34779f829901a664ac7c87d255b041af@google.com>

golang/net