http/spdy: add type to FlagClearPreviouslyPersistedSettings constant
http/spdy: add type to FlagClearPreviouslyPersistedSettings constant

R=rsc, bradfitz
CC=golang-dev
http://codereview.appspot.com/4436074

Committer: Russ Cox <5ad239cb8a44f659eaaee0aa1ea5b94947abe557@golang.org>

h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang