Rearrange generation of IETF QUIC STOP_SENDING frame.

Move the v99 version check from QuicControlFrameManager to QuicSession
and remove a delete call.  No functional change, not flag protected.

Merge internal change: 232860577

R=rch@chromium.org

Change-Id: I8340ea1eab8950cd21109585adcb0ef1d32c072d
Reviewed-on: https://chromium-review.googlesource.com/c/1471008
Reviewed-by: Ryan Hamilton <rch@chromium.org>
Commit-Queue: Ryan Hamilton <rch@chromium.org>
Cr-Commit-Position: refs/heads/master@{#632213}
3 files changed