golealk in the executor/loadremotetest

[hawkingrei]

Bug Report

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 goleak: Errors on successful test run: found unexpected goroutines:
[Goroutine 21290 in state select, with net/http.(*persistConn).writeLoop on top of the stack:
goroutine 21290 [select]:
net/http.(*persistConn).writeLoop(0xc0070bd440)
	GOROOT/src/net/http/transport.go:2410 +0x1a9
created by net/http.(*Transport).dialConn
	GOROOT/src/net/http/transport.go:1766 +0x261a
] 

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