[SPDY] Enable tests for SPDY/3.1 and SPDY/4a2

Make the sending of the initial stream window size part
of SpdySession::SendInitialSettings(). Since this is
already turned off for tests, this makes it a lot easier
to enable tests for SPDY/3.1 and above, since we don't
have to conditionally expect the initial WINDOW_UPDATE
frame.

Actually test handling of Alternate-Protocol header in
http_network_transaction_unittest.cc.

Fix handling of SPDY/3.1 and above in AlternateProtocolToString()
and HttpStreamFactoryImpl::GetAlternateProtocolRequestFor().

Other misc. cleanup.

BUG=230124
R=rch@chromium.org

Review URL: https://codereview.chromium.org/17760008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@208997 0039d316-1c4b-4281-b951-d872f2087c98
16 files changed